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Encyclopedia > Mars
Mars   Astronomical symbol of Mars
The planet Mars
Mars as seen by the Hubble Space Telescope
Epoch J2000
Aphelion 249,209,300 km
1.665861 AU
Perihelion 206,669,000 km
1.381497 AU
Semi-major axis 227,939,100 km
1.523679 AU
Eccentricity 0.093315
Orbital period 686.971 day

1.8808 Julian years
Look up Mars in Wiktionary, the free dictionary. ... Image File history File links Mars_symbol. ... Image File history File links Mars_Hubble. ... The Hubble Space Telescope (HST; also known colloquially as the Hubble or just Hubble) is a space telescope that was carried into Earth orbit by the Space Shuttle in April 1990. ... Two bodies with a slight difference in mass orbiting around a common barycenter. ... In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ... The J2000. ... A diagram of Keplerian orbital elements. ... The astronomical unit (AU or au or a. ... A diagram of Keplerian orbital elements. ... The semi-major axis of an ellipse In geometry, the term semi-major axis (also semimajor axis) is used to describe the dimensions of ellipses and hyperbolae. ... (This page refers to eccitricity in astrodynamics. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... In astronomy, a Julian year is a unit of time defined as exactly 365. ...

668.5991 sols
Synodic period 779.96 day
2.135 Julian years
Average orbital speed 24.077 km/s
Inclination 1.850°
5.65° to Sun's Equator
Longitude of ascending node 49.562°
Argument of perihelion 286.537°
Satellites 2
Physical characteristics
Equatorial radius 3,396.2 ± 0.1 km[a][2]
0.533 Earths
Polar radius 3,376.2 ± 0.1 km[a][2]
0.531 Earths
Flattening 0.00589 ± 0.00015
Surface area 144,798,500 km²
0.284 Earths
Volume 1.6318×1011 km³
0.151 Earths
Mass 6.4185×1023 kg
0.107 Earths
Mean density 3.934 g/cm³
Equatorial surface gravity 3.69 m/s²
0.376 g
Escape velocity 5.027 km/s
Sidereal rotation
period
1.025957 day
24.62296 h
Equatorial rotation velocity 868.22 km/h
Axial tilt 25.19°
North pole right ascension 21 h 10 min 44 s
317.68143°
North pole declination 52.88650°
Albedo 0.15
Surface temp.
   Kelvin
   Celsius
min mean max
186 K 227 K 268 K[4]
−87 °C −46 °C −5 °C
Apparent magnitude +1.8 to -2.91[3]
Angular diameter 3.5" — 25.1"[3]
Adjectives Martian
Atmosphere
Surface pressure 0.7–0.9 kPa
Composition 95.72% Carbon dioxide

2.7% Nitrogen
1.6% Argon
0.2% Oxygen
0.07% Carbon monoxide
0.03% Water vapor
0.01% Nitric oxide
2.5 ppm Neon
300 ppb Krypton
130 ppb Formaldehyde
80 ppb Xenon
30 ppb Ozone
Various schemes have been used or proposed to keep track of time and date on the planet Mars independently of Earth time and calendars. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... The orbital speed of a body, generally a planet, a natural satellite, an artificial satellite, or a multiple star, is the speed at which it orbits around the barycenter of a system, usually around a more massive body. ... For the science fiction novella by William Shunn, see Inclination (novella). ... Sol redirects here. ... World map showing the equator in red For other uses, see Equator (disambiguation). ... The Longitude of the ascending node (☊, also noted Ω) is one of the orbital elements used to specify the orbit of an object in space. ... The argument of periapsis (ω) is the orbital element describing the angle between an orbiting bodys ascending node (the point where the body crosses the plane of reference from South to North) and its periapsis (the point of closest approach to the central body), measured in the orbital plane and... A natural satellite or moon is a celestial body that orbits a planet or smaller body, which is called the primary. ... World map showing the equator in red For other uses, see Equator (disambiguation). ... A geographical pole is either of two fixed points on the surface of a spinning body or planet, at 90 degrees from the equator, based on the axis around which a body spins. ... The flattening, ellipticity, or oblateness of an oblate spheroid is the relative difference between its equatorial radius a and its polar radius b: The flattening of the Earth is 1:298. ... In mathematics, a spheroid is a quadric surface in three dimensions obtained by rotating an ellipse about one of its principal axes. ... For other uses, see Volume (disambiguation). ... For other uses, see Mass (disambiguation). ... For other uses, see Density (disambiguation). ... The surface gravity of a Killing horizon is the acceleration, as exerted at infinity, needed to keep an object at the horizon. ... Acceleration is the time rate of change of velocity and/or direction, and at any point on a velocity-time graph, it is given by the slope of the tangent to the curve at that point. ... The term g force or gee force refers to the symbol g, the force of acceleration due to gravity at the earths surface. ... Space Shuttle Atlantis launches on mission STS-71. ... In astronomy, a rotation period is the time an astronomical object takes to complete one revolution around its rotation axis relative to the background stars. ... In astronomy, axial tilt is the inclination angle of a planets rotational axis in relation to a perpendicular to its orbital plane. ... Equatorial Coordinates Right ascension (abbrev. ... In astronomy, declination (abbrev. ... For other uses, see Albedo (disambiguation). ... For other uses, see Temperature (disambiguation). ... For other uses, see Kelvin (disambiguation). ... For other uses, see Celsius (disambiguation). ... The apparent magnitude (m) of a star, planet or other celestial body is a measure of its apparent brightness as seen by an observer on Earth. ... The angular diameter of an object as seen from a given position is the diameter measured as an angle. ... This article is about hypothetical native inhabitants of the planet Mars. ... Atmospheric pressure is the pressure at any given point in the Earths atmosphere. ... For other uses, see Pascal. ... Carbon dioxide (chemical formula: ) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ... General Name, symbol, number argon, Ar, 18 Chemical series noble gases Group, period, block 18, 3, p Appearance colorless Standard atomic weight 39. ... This article is about the chemical element and its most stable form, or dioxygen. ... Carbon monoxide, with the chemical formula CO, is a colorless, odorless, and tasteless gas. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... R-phrases , , , , S-phrases , , , Except where noted otherwise, data are given for materials in their standard state (at 25 Â°C, 100 kPa) Infobox disclaimer and references Nitric oxide or Nitrogen monoxide is a chemical compound with chemical formula NO. This gas is an important signaling molecule in the body of... Parts per million (ppm) is a measure of concentration that is used where low levels of concentration are significant. ... For other uses, see Neon (disambiguation). ... This page refers to concentration in the chemical sense. ... For other uses, see Krypton (disambiguation). ... This page refers to concentration in the chemical sense. ... Formaldehyde is the chemical compound with the formula H2CO. It is the simplest aldehyde-- an organic compound containing a terminal carbonyl group: it consists of exactly one carbonyl. ... This page refers to concentration in the chemical sense. ... General Name, Symbol, Number xenon, Xe, 54 Chemical series noble gases Group, Period, Block 18, 5, p Appearance colorless Standard atomic weight 131. ... This page refers to concentration in the chemical sense. ... For other uses, see Ozone (disambiguation). ...

10 ppb Methane

Mars (pronounced [ˈmɑːz] (in British English) or [ˈmɑːrz] (in American English) ) is the fourth planet from the Sun in the Solar System. The planet is named after Mars, the Roman god of war. It is also referred to as the "Red Planet" because of its reddish appearance as seen from Earth. This page refers to concentration in the chemical sense. ... Methane is a chemical compound with the molecular formula . ... This article is about the astronomical term. ... Sol redirects here. ... This article is about the Solar System. ... Mars, painting by Diego Velazquez Mars was the Roman warrior god, the son of Juno and Jupiter, husband of Bellona, and the lover of Venus. ... A head of Minerva found in the ruins of the Roman baths in Bath Roman mythology, the mythological beliefs of the people of Ancient Rome, can be considered as having two parts. ... War Gods redirects here. ... This article is about Earth as a planet. ...


Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the volcanoes, valleys, deserts and polar ice caps of Earth. It is the site of Olympus Mons, the highest known mountain in the Solar System, and of Valles Marineris, the largest canyon. In addition to its geographical features, Mars’ rotational period and seasonal cycles are likewise similar to those of Earth. The inner planets, Mercury, Venus, Earth, and Mars, their sizes to scale. ... Atmospheres redirects here. ... Tycho crater on Earths moon. ... This article is about Earths moon. ... Cleveland Volcano in the Aleutian Islands of Alaska photographed from the International Space Station For other uses, see Volcano (disambiguation). ... Fljótsdalur in East Iceland, a rather flat valley In geology, a valley (also called a vale or dale) is a depression with predominant extent in one direction. ... This article is about arid terrain. ... This article or section does not cite its references or sources. ... This article is about the volcano on Mars and Solar Systems tallest mountain in Latin, For other uses, see Olympus (disambiguation). ... For other uses, see Mountain (disambiguation). ... Valles Marineris cuts a wide swath across the face of Mars Valles Marineris (Latin for Mariner Valley, named after the Mariner 9 Mars orbiter of 1971-72 which discovered it. ... In astronomy, a rotation period is the time an astronomical object takes to complete one revolution around its rotation axis. ... This article or section is in need of attention from an expert on the subject. ...


Until the first flyby of Mars by Mariner 4 in 1965, many speculated that there might be liquid water on the planet's surface. This was based on observations of periodic variations in light and dark patches, particularly in the polar latitudes, which looked like seas and continents, while long, dark striations were interpreted by some observers as irrigation channels for liquid water. These straight line features were later proven not to exist and were instead explained as optical illusions. Still, of all the planets in our Solar System other than Earth, Mars is the most likely to harbor liquid water, and perhaps life.[citation needed] Mariner 4 (Mariner-Mars 1964) was the fourth in a series of spacecraft used for planetary exploration in a flyby mode and performed the first successful flyby of the planet Mars, returning the first pictures of the Martian surface. ... For other uses, see Light (disambiguation). ... Dark redirects here. ... This article is about the geographical term. ... Bodybuilding In bodybuilding, striations are the tiny grooves of muscle across major muscle groups characteristic of a well-developed body. ... An optical illusion. ... This article is about life in general. ...


Mars is currently host to three functional orbiting spacecraft: Mars Odyssey, Mars Express, and Mars Reconnaissance Orbiter. This is more than any planet in the Solar System except Earth. The surface is also home to the two Mars Exploration Rovers (Spirit and Opportunity), the lander Phoenix, and several inert landers and rovers that either failed or completed missions. Geological evidence gathered by these and preceding missions suggests that Mars previously had large-scale water coverage, while observations also indicate that small geyser-like water flows have occurred in recent years.[5] Observations by NASA's Mars Global Surveyor show evidence that parts of the southern polar ice cap have been receding.[6] The Space Shuttle Discovery as seen from the International Space Station. ... Artists concept of the 2001 Mars Odyssey Spacecraft 2001 Mars Odyssey is an unmanned spacecraft orbiting the planet Mars. ... Concept model of the Mars Express spacecraft Main Engine Thrust for braking manouevre on Venus Express. ... NASAs Mars Reconnaissance Orbiter (MRO) is a multipurpose spacecraft designed to conduct reconnaissance and exploration of Mars from orbit. ... Artists Concept of Rover on Mars (credit: Maas Digital LLC) Marvin the Martian, Spirit rover Mission patch Duck Dodgers, Opportunity rover Mission patch NASAs Mars Exploration Rover (MER) Mission is an ongoing robotic mission of exploring Mars, that began in 2003 with the sending of two rovers â€” Spirit... The launch patch for Spirit, featuring Marvin the Martian. ... The launch patch for Opportunity, featuring Duck Dodgers (Daffy Duck). ... A lander is a type of spacecraft which descends to come to rest on the surface of an astronomical body. ... This article is about the Mars lander. ... Strokkur geyser, Iceland A geyser is a type of hot spring that erupts periodically, ejecting a column of hot water and steam into the air. ... For other uses, see NASA (disambiguation). ...


Mars has two moons, Phobos and Deimos, which are small and irregularly shaped. These may be captured asteroids, similar to 5261 Eureka, a Martian Trojan asteroid. Mars can be seen from Earth with the naked eye. Its apparent magnitude reaches −2.9,[3] a brightness surpassed only by Venus, the Moon, and the Sun, though most of the time Jupiter will appear brighter to the naked eye than Mars. A natural satellite or moon is a celestial body that orbits a planet or smaller body, which is called the primary. ... Phobos (IPA: or [ˈfoÊŠ.bÉ™s]) (systematic designation: ) is the larger and closer of Mars two moons (the other being Deimos). ... Deimos (IPA or ; Greek Δείμος: Dread), is the smaller and outermost of Mars’ two moons, named after Deimos from Greek Mythology. ... For other uses, see Asteroid (disambiguation). ... 5261 Eureka was discovered at Mt Palomar on June 20, 1990 and turned out to be the first known Mars Trojan asteroid. ... Image of the Trojan asteroids in front of and behind Jupiter along its orbital path. ... The apparent magnitude (m) of a star, planet or other celestial body is a measure of its apparent brightness as seen by an observer on Earth. ... For other uses, see Venus (disambiguation). ... For other uses, see Jupiter (disambiguation). ...

Contents

Physical characteristics

Size comparison of terrestrial planets (left to right): Mercury, Venus, Earth, and Mars.
Size comparison of terrestrial planets (left to right): Mercury, Venus, Earth, and Mars.

Mars has approximately half the radius of Earth and only one-tenth the mass, being less dense, but its surface area is only slightly less than the total area of Earth's dry land.[3] While Mars is larger and more massive than Mercury, Mercury has a higher density. This results in a slightly stronger gravitational force at Mercury's surface. The red-orange appearance of the Martian surface is caused by iron(III) oxide, more commonly known as hematite, or rust.[7] Image File history File linksMetadata Download high resolution version (1500x653, 488 KB)Terrestrial planet size comparisons. ... Image File history File linksMetadata Download high resolution version (1500x653, 488 KB)Terrestrial planet size comparisons. ... This article is about the planet. ... For other uses, see Venus (disambiguation). ... This article is about Earth as a planet. ... This article is about an authentication, authorization, and accounting protocol. ... For other uses, see Mass (disambiguation). ... Area is the measure of how much exposed area any two dimensional object has. ... This article is about the planet. ... Iron(III) oxide — also known as ferric oxide, Hematite, red iron oxide, synthetic maghemite, colcothar, or simply rust — is one of the several oxide compounds of iron, and has paramagnetic properties. ...


Geology

Main article: Geology of Mars

Based on orbital observations and the examination of the Martian meteorite collection, the surface of Mars appears to be composed primarily of basalt. Some evidence suggests that a portion of the Martian surface is more silica-rich than typical basalt, and may be similar to andesitic rocks on Earth; however, these observations may also be explained by silica glass. Much of the surface is deeply covered by a fine iron(III) oxide dust that has the consistency of talcum powder.[citation needed] False colour view of a landslide in Zunil crater The geology of Mars, also known as areology (from Greek: Ἂρης, Arēs, Ares; and λόγος, logos, knowledge), refers to the study of the composition, structure, physical properties, history and the processes that shape the planet Mars. ... A Martian meteorite is a meteorite that has landed on Earth but is believed to have originated from Mars. ... For the cities, see Basalt, Colorado and Basalt, Idaho. ... Andesite is an igneous, volcanic (extrusive) rock, of intermediate composition, with aphanitic to porphyritic texture. ... Iron(III) oxide — also known as ferric oxide, Hematite, red iron oxide, synthetic maghemite, colcothar, or simply rust — is one of the several oxide compounds of iron, and has paramagnetic properties. ... Talc block Talc is a mineral composed of hydrated magnesium silicate with the chemical formula H2Mg3(SiO3)4 or Mg3Si4O10(OH)2. ...

Rock strewn surface imaged by Mars Pathfinder
Rock strewn surface imaged by Mars Pathfinder

Although Mars has no intrinsic magnetic field, observations show that parts of the planet's crust have been magnetized and that alternating polarity reversals of its dipole field have occurred. This paleomagnetism of magnetically susceptible minerals has properties that are very similar to the alternating bands found on the ocean floors of Earth. One theory, published in 1999 and re-examined in October 2005 (with the help of the Mars Global Surveyor), is that these bands demonstrate plate tectonics on Mars 4 billion years ago, before the planetary dynamo ceased to function and caused the planet's magnetic field to fade away.[8] Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... The Mars Pathfinder was launched on December 4, 1996 by NASA aboard a Delta II just a month after the Mars Global Surveyor was launched. ... Paleomagnetism refers to the study of the record of the Earths magnetic field preserved in various magnetic minerals through time. ... The tectonic plates of the world were mapped in the second half of the 20th century. ... The Mars Global Surveyor (MGS) was a US spacecraft developed by NASA and the Jet Propulsion Laboratory and launched November 1996. ... The tectonic plates of the world were mapped in the second half of the 20th century. ... One thousand million (1,000,000,000) is the natural number following 999,999,999 and preceding 1,000,000,001. ... The Dynamo theory proposes a mechanism by which a celestial body such as the Earth generates a magnetic field. ...


Current models of the planet's interior imply a core region about 1,480 kilometres in radius, consisting primarily of iron with about 14–17% sulfur. This iron sulfide core is partially fluid, and has twice the concentration of the lighter elements than exist at Earth's core. The core is surrounded by a silicate mantle that formed many of the tectonic and volcanic features on the planet, but now appears to be inactive. The average thickness of the planet's crust is about 50 km, with a maximum thickness of 125 km.[9] Earth's crust, averaging 40 km, is only a third as thick as Mars’ crust relative to the sizes of the two planets. Fe redirects here. ... This article is about the chemical element. ... Iron(II) sulfide is a form of iron sulfide (others include iron pyrite aka Fools Gold), and can be obtained by reacting iron and sulfur under great heat. ... Earth cutaway from core to exosphere. ...


The geological history of Mars can be split into many epochs, but the following are the three main ones:

  • Noachian epoch (named after Noachis Terra): Formation of the oldest extant surfaces of Mars, 3.8 billion years ago to 3.5 billion years ago. Noachian age surfaces are scarred by many large impact craters. The Tharsis bulge volcanic upland is thought to have formed during this period, with extensive flooding by liquid water late in the epoch.
  • Hesperian epoch (named after Hesperia Planum): 3.5 billion years ago to 1.8 billion years ago. The Hesperian epoch is marked by the formation of extensive lava plains.
  • Amazonian epoch (named after Amazonis Planitia): 1.8 billion years ago to present. Amazonian regions have few meteorite impact craters but are otherwise quite varied. Olympus Mons formed during this period along with lava flows elsewhere on Mars.

A major geological event occurred on Mars on February 19, 2008, and was caught on camera by the Mars Reconnaissance Orbiter. Images capturing a spectacular avalanche of materials thought to be fine grained ice, dust, and large blocks are shown to have detached from a 2,300-foot (701 m) high cliff. Evidence of the avalanche is present in the dust clouds left above the cliff afterwards.[10] Noachis Terra (lit. ... Clouds hover over the volcano peaks of the Tharsis region in this color mosaic image. ... Amazonis Planitia is one of the smoothest plains on Mars. ... This article is about the volcano on Mars and Solar Systems tallest mountain in Latin, For other uses, see Olympus (disambiguation). ... [[Media:Italic text]]{| style=float:right; |- | |- | |} is the 50th day of the year in the Gregorian calendar. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance with the Gregorian calendar. ... NASAs Mars Reconnaissance Orbiter (MRO) is a multipurpose spacecraft designed to conduct reconnaissance and exploration of Mars from orbit. ...


Hydrology

Photo of microscopic rock forms indicating past signs of water, taken by Opportunity
Photo of microscopic rock forms indicating past signs of water, taken by Opportunity

Liquid water cannot exist on the surface of Mars with its present low atmospheric pressure, except at the lowest elevations for short periods[11][12] but water ice is in no short supply, with two polar ice caps made largely of ice.[13] In March 2007, NASA announced that the volume of water ice in the south polar ice cap, if melted, would be sufficient to cover the entire planetary surface to a depth of 11 metres.[14] Additionally, an ice permafrost mantle stretches down from the pole to latitudes of about 60°.[13] This image taken by MER-B (Mars Rover Opportunity) shows microscopic rock forms indicating past signs of water on Mars. ... This image taken by MER-B (Mars Rover Opportunity) shows microscopic rock forms indicating past signs of water on Mars. ... The launch patch for Opportunity, featuring Duck Dodgers (Daffy Duck). ... While these two men dig in Alaska to study soil, the hard permafrost requires the use of a jackhammer In geology, permafrost or permafrost soil is soil at or below the freezing point of water (0 °C or 32 °F) for two or more years. ...


Much larger quantities of water are thought to be trapped underneath Mars's thick cryosphere, only to be released when the crust is cracked through volcanic action. The largest such release of liquid water is thought to have occurred when the Valles Marineris formed early in Mars's history, enough water being released to form the massive outflow channels. A smaller but more recent event of the same kind may have occurred when the Cerberus Fossae chasm opened about 5 million years ago, leaving a supposed sea of frozen ice still visible today on the Elysium Planitia centered at Cerberus Palus.[15] However, the morphology of this region is more consistent with the ponding of lava flows causing a superficial similarity to ice flows.[16] These lava flows probably draped the terrain established by earlier catastrophic floods of Athabasca Valles.[17] Significantly rough surface texture at decimeter (dm) scales, thermal inertia comparable to that of the Gusev plains, and hydrovolcanic cones are consistent with the lava flow hypothesis.[17] Furthermore, the stoichiometric mass fraction of H2O in this area to tens of centimeter depths is only ~4%,[18] easily attributable to hydrated minerals[19] and inconsistent with the presence of near-surface ice. The cryosphere, derived from the Greek word kryos for frost or icy cold, is the term which collectively describes the portions of the Earth’s surface where water is in solid form, including sea ice, lake ice, river ice, snow cover, glaciers, ice caps and ice sheets, and frozen ground... Valles Marineris cuts a wide swath across the face of Mars Valles Marineris (Latin for Mariner Valley, named after the Mariner 9 Mars orbiter of 1971-72 which discovered it. ... A 3km section of the Cerberus Fossae fissure, taken by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) The Cerberus Fossae are a series of semi-parallel fissures on Mars formed by faults which pulled the crust apart in the Cerberus region(9°N, 197°W). ... Look up million in Wiktionary, the free dictionary. ... Elysium Planitia is the second largest volcanic region on Mars, after Tharsis Montes. ...


More recently the high resolution Mars Orbiter Camera on the Mars Global Surveyor has taken pictures which give much more detail about the history of liquid water on the surface of Mars. Despite the many giant flood channels and associated tree-like network of tributaries found on Mars there are no smaller scale structures that would indicate the origin of the flood waters. It has been suggested that weathering processes have denuded these, indicating the river valleys are old features. Higher resolution observations from spacecraft like Mars Global Surveyor also revealed at least a few hundred features along crater and canyon walls that appear similar to terrestrial seepage gullies. The gullies tend to be in the highlands of the southern hemisphere and to face the Equator; all are poleward of 30° latitude.[20] The researchers found no partially degraded (i.e. weathered) gullies and no superimposed impact craters, indicating that these are very young features. The Mars Global Surveyor (MGS) was a US spacecraft developed by NASA and the Jet Propulsion Laboratory and launched November 1996. ...

Changing gully deposits on Mars

In a particularly striking example (see image) two photographs, taken six years apart, show a gully on Mars with what appears to be new deposits of sediment. Michael Meyer, the lead scientist for NASA's Mars Exploration Program, argues that only the flow of material with a high liquid water content could produce such a debris pattern and colouring. Whether the water results from precipitation, underground or another source remains an open question.[21] However, alternative scenarios have been suggested, including the possibility of the deposits being caused by carbon dioxide frost or by the movement of dust on the Martian surface.[22][23] Image File history File links Wateronmars. ... Image File history File links Wateronmars. ...


Further evidence that liquid water once existed on the surface of Mars comes from the detection of specific minerals such as hematite and goethite, both of which sometimes form in the presence of water.[24] For other uses, see Liquid (disambiguation). ... For other uses, see Hematite (disambiguation). ... Goethite, named after the German polymath Johann Wolfgang von Goethe, is an iron bearing oxide mineral found in soil and other low temperature environments. ...


Nevertheless, some of the evidence believed to indicate ancient water basins and flows has been negated by higher resolution studies taken at resolution about 30 cm by the Mars Reconnaissance Orbiter.[25]


Geography

See also: Category:Surface features of Mars
This approximate true-color image, taken by the Mars Exploration Rover Opportunity, shows the view of Victoria Crater from Cape Verde. It was captured over a three-week period, from October 16 - November 6, 2006.
This approximate true-color image, taken by the Mars Exploration Rover Opportunity, shows the view of Victoria Crater from Cape Verde. It was captured over a three-week period, from October 16 - November 6, 2006.

Although better remembered for mapping the Moon, Johann Heinrich Mädler and Wilhelm Beer were the first "areographers". They began by establishing once and for all that most of Mars’ surface features were permanent, and determining the planet's rotation period. In 1840, Mädler combined ten years of observations and drew the first map of Mars. Rather than giving names to the various markings, Beer and Mädler simply designated them with letters; Meridian Bay (Sinus Meridiani) was thus feature "a."[26] Topographic map of Mars, courtesy NASA Goddard Space Flight Center, from Mars Global Surveyor laser altimeter research led by Maria Zuber and David Smith. ... This is a list of all the named mountains on Mars. ... There are hundreds of thousands of craters on Mars, but only some of them have names. ... The launch patch for Opportunity, featuring Duck Dodgers (Daffy Duck). ... Victoria Crater is an impact crater located at 5. ... J. H. von Mädler. ... Wilhelm Beer Wilhelm Wolff Beer (January 14, 1797 – March 27, 1850) was a banker and astronomer in Berlin, Germany, and brother of Giacomo Meyerbeer. ...


Today, features on Mars are named from a number of sources. Large albedo features retain many of the older names, but are often updated to reflect new knowledge of the nature of the features. For example, Nix Olympica (the snows of Olympus) has become Olympus Mons (Mount Olympus).[27] For other uses, see Albedo (disambiguation). ...


Mars’ equator is defined by its rotation, but the location of its Prime Meridian was specified, as was Earth's (at Greenwich), by choice of an arbitrary point; Mädler and Beer selected a line in 1830 for their first maps of Mars. After the spacecraft Mariner 9 provided extensive imagery of Mars in 1972, a small crater (later called Airy-0), located in the Sinus Meridiani ("Middle Bay" or "Meridian Bay"), was chosen for the definition of 0.0° longitude to coincide with the original selection. Location of the Prime Meridian Image:Prime Meridian. ... This article is about Greenwich in England. ... Mariner 9 launch Mariner 9 (Mariner Mars 71 / Mariner-I) was a NASA space probe orbiter that helped in the exploration of Mars and was part of the Mariner program. ... Airy-0 is a crater on Mars whose location defines the position of the prime meridian of that planet. ... Sinus Meridiani is a classic albedo feature on Mars stretching east-west just south of that planets equator. ...

Since Mars has no oceans and hence no 'sea level', a zero-elevation surface or mean gravity surface also had to be selected. Zero altitude is defined by the height at which there is 610.5 Pa (6.105 mbar) of atmospheric pressure. This pressure corresponds to the triple point of water, and is about 0.6% of the sea level surface pressure on Earth.[28] Image File history File links Download high resolution version (692x1448, 852 KB) Olympus Mons on October 19, 1998, image by the Mars Global Surveyor. ... Image File history File links Download high resolution version (692x1448, 852 KB) Olympus Mons on October 19, 1998, image by the Mars Global Surveyor. ... This article is about the volcano on Mars and Solar Systems tallest mountain in Latin, For other uses, see Olympus (disambiguation). ... Zero-elevation surface is a widely-accepted vertical reference point that is used to describe a surface, such as that of a planet. ... For other uses, see Pascal. ... In physics, the triple point of a substance is the temperature and pressure at which three phases (gas, liquid, and solid) of that substance may coexist in thermodynamic equilibrium. ...


The dichotomy of Martian topography is striking: northern plains flattened by lava flows contrast with the southern highlands, pitted and cratered by ancient impacts. The surface of Mars as seen from Earth is thus divided into two kinds of areas, with differing albedo. The paler plains covered with dust and sand rich in reddish iron oxides were once thought of as Martian 'continents' and given names like Arabia Terra (land of Arabia) or Amazonis Planitia (Amazonian plain). The dark features were thought to be seas, hence their names Mare Erythraeum, Mare Sirenum and Aurorae Sinus. The largest dark feature seen from Earth is Syrtis Major.[29] Arabia Terra is large upland region in the north of Mars. ... Amazonis Planitia is one of the smoothest plains on Mars. ... Mare Erythraeum is a dark dusky region of Mars that can be viewed by even a small telescope. ... a like dark place in the sky. ... Syrtis Major is a dark spot (an albedo feature) located in the boundary between the northern lowlands and southern highlands of Mars. ...


The shield volcano, Olympus Mons (Mount Olympus), at 26 km is the highest known mountain in the Solar System. It is an extinct volcano in the vast upland region Tharsis, which contains several other large volcanoes. It is over three times the height of Mount Everest which in comparison stands at only 8.848 km. Shield volcano A shield volcano is a large volcano with shallow-sloping sides. ... This article is about the volcano on Mars and Solar Systems tallest mountain in Latin, For other uses, see Olympus (disambiguation). ... Clouds hover over the volcano peaks of the Tharsis region in this color mosaic image. ... Everest redirects here. ...


Mars is also scarred by a number of impact craters: a total of 43,000 craters with a diameter of 5 km or greater have been found.[30] The largest of these is the Hellas impact basin, a light albedo feature clearly visible from Earth.[31] Due to the smaller mass of Mars, the probability of an object colliding with the planet is about half that of the Earth. However, Mars is located closer to the asteroid belt, so it has an increased chance of being struck by materials from that source. Mars is also more likely to be struck by short-period comets, i.e., those that lie within the orbit of Jupiter.[32] In spite of this, there are far fewer craters on Mars compared with the Moon because Mars's atmosphere provides protection against small meteors. Some craters have a morphology that suggests the ground was wet when the meteor impacted. Tycho crater on Earths moon. ... NASA image of Hellas Planitia Hellas Planitia, also known as the Hellas Impact Basin, is a roughly circular impact crater located in the southern hemisphere of the planet Mars. ... An albedo feature is a large area on the surface of a planet (or other solar system body) which shows a contrast in brightness or darkness (albedo) with adjacent areas. ... Comet Hale-Bopp Comet West For other uses, see Comet (disambiguation). ... This article is about Earths moon. ...


The large canyon, Valles Marineris (Latin for Mariner Valleys, also known as Agathadaemon in the old canal maps), has a length of 4000 km and a depth of up to 7 km. The length of Valles Marineris is equivalent to the length of Europe and extends across one-fifth the circumference of Mars. By comparison, the Grand Canyon on Earth is only 446 km long and nearly 2 km deep. Valles Marineris was formed due to the swelling of the Tharis area which caused the crust in the area of Valles Marineris to collapse. Another large canyon is Ma'adim Vallis (Ma'adim is Hebrew for Mars). It is 700 km long and again much bigger than the Grand Canyon with a width of 20 km and a depth of 2 km in some places. It is possible that Ma'adim Vallis was flooded with liquid water in the past.[33] Valles Marineris cuts a wide swath across the face of Mars Valles Marineris (Latin for Mariner Valley, named after the Mariner 9 Mars orbiter of 1971-72 which discovered it. ... Launch of Mariner 1 (NASA) The Mariner program was a program conducted by the American space agency NASA that launched a series of robotic interplanetary probes designed to investigate Mars, Venus and Mercury. ... This article is about the canyon in the southwestern United States. ... Maadim Vallis is one of the largest canyons on Mars, about 700 kilometers long and significantly larger than Earths Grand Canyon. ... The word Hebrew most likely means to cross over, referring to the Semitic people crossing over the Euphrates River. ...

THEMIS image of cave entrances on Mars
THEMIS image of cave entrances on Mars

Images from the Thermal Emission Imaging System (THEMIS) aboard NASA's Mars Odyssey orbiter have revealed seven possible cave entrances on the flanks of the Arsia Mons volcano.[34] The caves, named Dena, Chloe, Wendy, Annie, Abbey, Nikki and Jeanne after loved ones of their discoverers, are collectively known as the "seven sisters."[35] Cave entrances measure from 100 m to 252 m wide and they are believed to be at least 73 m to 96 m deep. Because light does not reach the floor of most of the caves, it is likely that they extend much deeper than these lower estimates and widen below the surface. Dena is the only exception; its floor is visible and was measured to be 130 m deep. The interiors of these caverns may be protected from micrometeoroids, UV radiation, solar flares and high energy particles that bombard the planet's surface.[36] Some researchers have suggested that this protection makes the caves good candidates for future efforts to find liquid water and signs of life. A THEMIS spectrometer The Thermal Emission Imaging System (THEMIS) is a camera that images Mars in the visible and infrared parts of the spectrum in order to determine the distribution of minerals on the surface of Mars. ... 2001 Mars Odyssey is a robotic spacecraft orbiting the planet Mars. ... For other uses, see Cave (disambiguation). ... Courtesy NASA/JPL-Caltech Arsia Mons is the southernmost of three volcanos (collectively known as Tharsis Montes) on the Tharsis bulge near the equator of the planet Mars. ... A solar flare observed by Hinode in the G-band. ...


Mars has two permanent polar ice caps: the northern one at Planum Boreum and the southern one at Planum Australe. Viking mosaic of Planum Boreale and surrounds. ... Planum Australe, taken by Mars Global Surveyor. ...


Atmosphere

Main article: Atmosphere of Mars
Mars's thin atmosphere, visible on the horizon in this low-orbit photo.
Mars's thin atmosphere, visible on the horizon in this low-orbit photo.

Mars lost its magnetosphere 4 billion years ago, so the solar wind interacts directly with the Martian ionosphere, keeping the atmosphere thinner than it would otherwise be by stripping away atoms from the outer layer. Both Mars Global Surveyor and Mars Express have detected these ionised atmospheric particles trailing off into space behind Mars.[37][38] The atmosphere of Mars is now relatively thin. Atmospheric pressure on the surface varies from around 30 Pa (0.03 kPa) on Olympus Mons to over 1155 Pa (1.155 kPa) in the depths of Hellas Planitia, with a mean surface level pressure of 600 Pa (0.6 kPa). This is less than 1% of the surface pressure on Earth (101.3 kPa). Mars's mean surface pressure equals the pressure found 35 km above the Earth's surface. The scale height of the atmosphere, about 11 km, is higher than Earth's (6 km) due to the lower gravity. Mars, the fourth planet from the Sun, has a very different atmosphere from that of Earth. ... Image File history File links Size of this preview: 534 × 600 pixel Image in higher resolution (1047 × 1176 pixel, file size: 114 KB, MIME type: image/jpeg) Atmosphere of Mars taken from low orbit. ... Image File history File links Size of this preview: 534 × 600 pixel Image in higher resolution (1047 × 1176 pixel, file size: 114 KB, MIME type: image/jpeg) Atmosphere of Mars taken from low orbit. ... A magnetosphere is the region around an astronomical object in which phenomena are dominated or organized by its magnetic field. ... The plasma in the solar wind meeting the heliopause The solar wind is a stream of charged particles (i. ... Relationship of the atmosphere and ionosphere The ionosphere is the uppermost part of the atmosphere, distinguished because it is ionized by solar radiation. ... The Mars Global Surveyor (MGS) was a US spacecraft developed by NASA and the Jet Propulsion Laboratory and launched November 1996. ... Atmosphere is the general name for a layer of gases that may surround a material body of sufficient mass. ... Atmospheric pressure is the pressure at any given point in the Earths atmosphere. ... For other uses, see Pascal. ... NASA image of Hellas Planitia Hellas Planitia, also known as the Hellas Impact Basin, is a roughly circular impact crater located in the southern hemisphere of the planet Mars. ... A scale height is a term often used in scientific contexts for a distance over which a quantity decreases by a factor of e. ...


The atmosphere on Mars consists of 95% carbon dioxide, 3% nitrogen, 1.6% argon, and contains traces of oxygen and water.[3] The atmosphere is quite dusty, containing particulates about 1.5 µm in diameter which give the Martian sky a tawny color when seen from the surface.[39] Carbon dioxide (chemical formula: ) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ... General Name, symbol, number argon, Ar, 18 Chemical series noble gases Group, period, block 18, 3, p Appearance colorless Standard atomic weight 39. ... This article is about the chemical element and its most stable form, or dioxygen. ... A micrometre (American spelling: micrometer, symbol µm) is an SI unit of length. ... In heraldry, tenné or tawny is a stain, a rarely used tincture, an orangish brown colour. ...


Several researchers claim to have detected methane in the Martian atmosphere with a concentration of about 10 ppb by volume.[40][41] Since methane is an unstable gas that is broken down by ultraviolet radiation, typically lasting about 340 years in the Martian atmosphere,[42] its presence would indicate a current or recent source of the gas on the planet. Volcanic activity, cometary impacts, and the presence of methanogenic microbial life forms are among possible sources. It was recently pointed out that methane could also be produced by a non-biological process called serpentinization[b] involving water, carbon dioxide, and the mineral olivine, which is known to be common on Mars.[43] Methane is a chemical compound with the molecular formula . ... This page refers to concentration in the chemical sense. ... For other uses, see Gas (disambiguation). ... For other uses, see Ultraviolet (disambiguation). ... This article is about volcanoes in geology. ... Comet Hale-Bopp Comet West For other uses, see Comet (disambiguation). ... Methanogens are archaea that produce methane as a metabolic byproduct in anoxic conditions. ... A cluster of Escherichia coli bacteria magnified 10,000 times. ... A sample of serpentinite rock, partially made up of chrysotile Serpentinite is a rock comprised of one or more serpentine minerals. ... For other uses, see Mineral (disambiguation). ... The mineral olivine (also called chrysolite and, when gem-quality, peridot) is a magnesium iron silicate with the formula (Mg,Fe)2SiO4. ...


During a pole's winter, it lies in continuous darkness, chilling the surface and causing 25–30% of the atmosphere to condense out into thick slabs of CO2 ice (dry ice).[44] When the poles are again exposed to sunlight, the frozen CO2 sublimes, creating enormous winds that sweep off the poles as fast as 400 km/h. These seasonal actions transport large amounts of dust and water vapor, giving rise to Earth-like frost and large cirrus clouds. Clouds of water-ice were photographed by the Opportunity rover in 2004.[45] Carbon dioxide (chemical formula: ) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... Dry ice pellet sublimating in water Dry ice block sublimating in air. ... Sublimation of an element or substance is a conversion between the solid and the gas phases with no intermediate liquid stage. ... Frost on black pipes Frost is a solid deposition of water vapor from saturated air. ... This article is about cirrus clouds. ... The launch patch for Opportunity, featuring Duck Dodgers (Daffy Duck). ...


Climate

Main article: Climate of Mars
Mars from Hubble Space Telescope October 28, 2005 with dust storm visible.
Mars from Hubble Space Telescope October 28, 2005 with dust storm visible.

Of all the planets, Mars's seasons are the most Earth-like, due to the similar tilts of the two planets' rotational axes. However, the lengths of the Martian seasons are about twice those of Earth's, as Mars’ greater distance from the Sun leads to the Martian year being about two Earth years in length. Martian surface temperatures vary from lows of about −140 °C (-220 °F) during the polar winters to highs of up to 20 °C (68 °F) in summers.[11] The wide range in temperatures is due to the thin atmosphere which cannot store much solar heat, the low atmospheric pressure, and the low thermal inertia of Martian soil.[46] Mars has a reasonably well studied climate, starting in earnest with the Viking program in 1975 and continuing with such probes as the highly successful Mars Global Surveyor. ... Image File history File links Download high resolution version (700x700, 34 KB) NASAs Hubble Space Telescope snapped this picture of Mars on October 28, within a day of its closest approach to Earth on the night of October 29. ... Image File history File links Download high resolution version (700x700, 34 KB) NASAs Hubble Space Telescope snapped this picture of Mars on October 28, within a day of its closest approach to Earth on the night of October 29. ... The Hubble Space Telescope (HST; also known colloquially as the Hubble or just Hubble) is a space telescope that was carried into Earth orbit by the Space Shuttle in April 1990. ... is the 301st day of the year (302nd in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... For other uses, see Celsius (disambiguation). ... Volumetric heat capacity (VHC) describes the ability of a given volume of a substance to store heat while undergoing a given temperature change, but without undergoing a phase change. ...


If Mars had an Earth-like orbit, its seasons would be similar to Earth's because its axial tilt is similar to Earth's. However, the comparatively large eccentricity of the Martian orbit has a significant effect. Mars is near perihelion when it is summer in the southern hemisphere and winter in the north, and near aphelion when it is winter in the southern hemisphere and summer in the north. As a result, the seasons in the southern hemisphere are more extreme and the seasons in the northern are milder than would otherwise be the case. The summer temperatures in the south can be up to 30 °C (54 °F) warmer than the equivalent summer temperatures in the north.[47] A diagram of Keplerian orbital elements. ... A diagram of Keplerian orbital elements. ...

Mars's northern ice cap.
Mars's northern ice cap.

Mars also has the largest dust storms in our Solar System. These can vary from a storm over a small area, to gigantic storms that cover the entire planet. They tend to occur when Mars is closest to the Sun, and have been shown to increase the global temperature.[48] North Polar region of Mars; http://photojournal. ... North Polar region of Mars; http://photojournal. ... “Sandstorm” redirects here. ...


The polar caps at both poles consist primarily of water ice. However, there is dry ice present on their surfaces. Frozen carbon dioxide (dry ice) accumulates as a thin layer about one metre thick on the north cap in the northern winter only, while the south cap has a permanent dry ice cover about eight metres thick.[49] The northern polar cap has a diameter of about 1,000 kilometres during the northern Mars summer,[50] and contains about 1.6 million cubic kilometres of ice, which if spread evenly on the cap would be 2 kilometres thick.[51] (This compares to a volume of 2.85 million cubic kilometres for the Greenland ice sheet.) The southern polar cap has a diameter of 350 km and a thickness of 3 km.[52] The total volume of ice in the south polar cap plus the adjacent layered deposits has also been estimated at 1.6 million cubic kilometres.[53] Both polar caps show spiral troughs, which are believed to form as a result of differential solar heating, coupled with the sublimation of ice and condensation of water vapor.[54][55] Both polar caps shrink and regrow following the temperature fluctuation of the Martian seasons. Outline Map of Greenland with ice sheet depths. ...


Orbit and rotation

Mars’ average distance from the Sun is roughly 230 million km (1.5 AU) and its orbital period is 687 (Earth) days. The solar day (or sol) on Mars is only slightly longer than an Earth day: 24 hours, 39 minutes, and 35.244 seconds. A Martian year is equal to 1.8809 Earth years, or 1 year, 320 days, and 18.2 hours. Various schemes have been used or proposed to keep track of time and date on the planet Mars independently of Earth time and calendars. ...


Mars's axial tilt is 25.19 degrees, which is similar to the axial tilt of the Earth. As a result, Mars has seasons like the Earth, though on Mars they are about twice as long given its longer year. Mars passed its perihelion in June 2007 and its aphelion in May 2008.


Mars has a relatively pronounced orbital eccentricity of about 0.09; of the seven other planets in the Solar System, only Mercury shows greater eccentricity. However, it is known that in the past Mars has had a much more circular orbit than it does currently. At one point 1.35 million Earth years ago, Mars had an eccentricity of roughly 0.002, much less than that of Earth today.[56] The Mars cycle of eccentricity is 96,000 Earth years compared to the Earth's cycle of 100,000 years.[57] However, Mars also has a much longer cycle of eccentricity with a period of 2.2 million Earth years, and this overshadows the 96,000 year cycle in the eccentricity graphs. For the last 35,000 years Mars' orbit has been getting slightly more eccentric because of the gravitational effects of the other planets. The closest distance between the Earth and Mars will continue to mildly decrease for the next 25,000 years.[58] (This page refers to eccitricity in astrodynamics. ... This article is about the planet. ...

The image to the left shows a comparison between Mars and Ceres, a dwarf planet in the Asteroid Belt, as seen from the ecliptic pole, while the image to the right is as seen from the ascending node. The segments of orbits below the ecliptic are plotted in darker colors. The perihelia (q) and aphelia (Q) are labelled with the date of the nearest passage. Image File history File links ThePlanets_Orbits_Ceres_Mars_PolarView. ... Image File history File links ThePlanets_Orbits_Ceres_Mars. ... 1 Ceres (IPA , Latin: ) is a dwarf planet in the asteroid belt. ... Artists impression of Pluto (background) and Charon (foreground). ... For other uses, see Asteroid (disambiguation). ... The plane of the ecliptic is well seen in this picture from the 1994 lunar prospecting Clementine spacecraft. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ...

Moons

Main article: Moons of Mars
Phobos (left) and Deimos (right)
Phobos (left) and Deimos (right)

Mars has two tiny natural moons, Phobos and Deimos, which orbit very close to the planet and are thought to be captured asteroids.[59] The relative sizes of and distance between Mars, Phobos, and Deimos, to scale : Phobos (top) and Deimos (bottom). ... Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Phobos (IPA: or [ˈfoÊŠ.bÉ™s]) (systematic designation: ) is the larger and closer of Mars two moons (the other being Deimos). ... Deimos (IPA or ; Greek Δείμος: Dread), is the smaller and outermost of Mars’ two moons, named after Deimos from Greek Mythology. ...


Both satellites were discovered in 1877 by Asaph Hall, and are named after the characters Phobos (panic/fear) and Deimos (terror/dread) who, in Greek mythology, accompanied their father Ares, god of war, into battle. Ares was known as Mars to the Romans.[60] Asaph Hall (October 15, 1829 – November 22, 1907) was an American astronomer who is most famous for having discovered the moons of Mars (namely Deimos and Phobos) in 1877. ... In Greek mythology, Phobos (fright) was the personification of fear and horror. ... In Greek mythology, Deimos (dread) was the personification of dread. ... The bust of Zeus found at Otricoli (Sala Rotonda, Museo Pio-Clementino, Vatican) Greek mythology is the body of stories belonging to the Ancient Greeks concerning their gods and heroes, the nature of the world and the origins and significance of their own cult and ritual practices. ... This article is about the ancient Greek god. ...


From the surface of Mars, the motions of Phobos and Deimos appear very different from that of our own moon. Phobos rises in the west, sets in the east, and rises again in just 11 hours. Deimos, being only just outside synchronous orbit—where the orbital period would match the planet's period of rotation—rises as expected in the east but very slowly. Despite the 30 hour orbit of Deimos, it takes 2.7 days to set in the west as it slowly falls behind the rotation of Mars, then just as long again to rise.[61] A synchronous orbit is an orbit in which an orbiting body (usually a satellite) has a period equal to the average rotational period of the body being orbited (usually a planet), and in the same direction of rotation as that body. ...


Because Phobos' orbit is below synchronous altitude, the tidal forces from the planet Mars are gradually lowering its orbit. In about 50 million years it will either crash into Mars’ surface or break up into a ring structure around the planet.[61] Comet Shoemaker-Levy 9 after breaking up under the influence of Jupiters tidal forces. ...


It is not well understood how or when Mars came to capture its two moons. Both have circular orbits, very near the equator, which is very unusual in itself for captured objects. Phobos's unstable orbit would seem to point towards a relatively recent capture. There is no known mechanism for an airless Mars to capture a lone asteroid, so it is likely that a third body was involved—however, asteroids as large as Phobos and Deimos are rare, and binaries rarer still, outside the asteroid belt.[62] In astrodynamics or celestial mechanics a circular orbit is an elliptic orbit with the eccentricity equal to 0. ...


Life

Main article: Life on Mars

The current understanding of planetary habitability—the ability of a world to develop and sustain life—favors planets that have liquid water on their surface. This requires that the orbit of a planet lie within a habitable zone, which for the Sun is currently occupied by Earth. Mars orbits half an astronomical unit beyond this zone and this, along with the planet's thin atmosphere, causes water to freeze on its surface. The past flow of liquid water, however, demonstrates the planet's potential for habitability. Recent evidence has suggested that any water on the Martian surface would have been too salty and acidic to support life.[63] For other uses, see Life on Mars (disambiguation). ... Understanding planetary habitability is partly an extrapolation of the Earths conditions, as it is the only planet currently known to support life. ... It has been suggested that Goldilocks phenomenon be merged into this article or section. ... The astronomical unit (AU or au or a. ...


The lack of a magnetosphere and extremely thin atmosphere of Mars are a greater challenge: the planet has little heat transfer across its surface, poor insulation against bombardment and the solar wind, and insufficient atmospheric pressure to retain water in a liquid form (water instead sublimates to a gaseous state). Mars is also nearly, or perhaps totally, geologically dead; the end of volcanic activity has stopped the recycling of chemicals and minerals between the surface and interior of the planet.[64] In thermal physics, heat transfer is the passage of thermal energy from a hot to a colder body. ... The plasma in the solar wind meeting the heliopause The solar wind is a stream of charged particles (i. ...


Evidence suggests that the planet was once significantly more habitable than it is today, but whether living organisms ever existed there is still unclear. The Viking probes of the mid-1970s carried experiments designed to detect microorganisms in Martian soil at their respective landing sites, and had some apparently positive results, including a temporary increase of CO2 production on exposure to water and nutrients. However this sign of life was later disputed by many scientists, resulting in a continuing debate, with NASA scientist Gilbert Levin asserting that Viking may have found life. A re-analysis of the now 30-year-old Viking data, in light of modern knowledge of extremophile forms of life, has suggested that the Viking tests were also not sophisticated enough to detect these forms of life. The tests may even have killed a (hypothetical) life form.[65] Domains and Kingdoms Nanobes Acytota Cytota Bacteria Neomura Archaea Eukaryota Bikonta Apusozoa Rhizaria Excavata Archaeplastida Rhodophyta Glaucophyta Plantae Heterokontophyta Haptophyta Cryptophyta Alveolata Unikonta Amoebozoa Opisthokonta Choanozoa Fungi Animalia An ericoid mycorrhizal fungus Life on Earth redirects here. ... Viking mission profile. ... –Gilbert Levin is an American engineer, the founder of Spherix and famous for experiments on Mars soil and the development of tagatose. ... An extremophile is an organism, usually unicellular, which thrives in or requires extreme conditions that would exceed optimal conditions for growth and reproduction in the majority of mesophilic terrestrial organisms. ...


At the Johnson space center lab organic compounds have been found in the meteorite ALH84001, which is supposed to have come from Mars. They concluded that these were deposited by primitive life forms extant on Mars before the meteorite was blasted into space by a meteor strike and sent on a 15 million-year voyage to Earth. Also, small quantities of methane and formaldehyde recently detected by Mars orbiters are both claimed to be hints for life, as these chemical compounds would quickly break down in the Martian atmosphere.[66][67] It is possible that these compounds may be replenished by volcanic or geological means such as serpentinization.[43] An aerial view of the complete Johnson Space Center facility in Houston, Texas in 1989. ... Willamette Meteorite A meteorite is a natural object originating in outer space that survives an impact with the Earths surface without being destroyed. ... Meteorite fragment ALH84001 ALH 84001 (Allan Hills 84001) is a meteorite found in Allan Hills, Antarctica in December 1984 by a team of US meteorite hunters from the ANSMET project. ... Methane is a chemical compound with the molecular formula . ... Formaldehyde is the chemical compound with the formula H2CO. It is the simplest aldehyde-- an organic compound containing a terminal carbonyl group: it consists of exactly one carbonyl. ... A chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by mass. ... Serpentinization is a geological metamorphic process involving heat and water in which low-silica mafic and ultramafic rocks are oxidized and hydrolyzed with water into serpentinite. ...


Exploration

Main article: Exploration of Mars
Mars 3 Lander (stamp, 1972)
Mars 3 Lander (stamp, 1972)

Dozens of spacecraft, including orbiters, landers, and rovers, have been sent to Mars by the Soviet Union, the United States, Europe, and Japan to study the planet's surface, climate, and geology. Computer-generated image of one of the two Mars Exploration Rovers which touched down on Mars in 2004. ... It has been suggested that this article or section be merged with Mars 2. ... Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Viking 1 was the first of two spacecraft sent to Mars as part of NASAs Viking program, and holds the record for the longest Mars surface mission of 4 years and 28 days (from landing until mission termination). ... The Space Shuttle Discovery as seen from the International Space Station. ... An orbiter is a spacecraft that orbits a planet or moon without landing on it in order to study the objects surface from a safe distance. ... This article is about the spacecraft type. ... Two different Mars rover designs. ... This article is about the European Space Agency. ... The Japan Aerospace eXploration Agency (JAXA) is Japans aerospace agency. ...


Roughly two-thirds of all spacecraft destined for Mars have failed in one manner or another before completing or even beginning their missions. While this high failure rate can be ascribed to technical problems, enough have either failed or lost communications for causes unknown for some to search for other explanations. Examples include an Earth-Mars "Bermuda Triangle", a Mars Curse, or even the long-standing NASA in-joke, the "Great Galactic Ghoul" that feeds on Martian spacecraft.[68] NASA image of the western Atlantic, showing the popular borders of the Bermuda Triangle. ... Computer-generated image of one of the two Mars Exploration Rovers which touched down on Mars in 2004. ... The Great Galactic Ghoul is a fictional space monster that consumes Mars probes. ...


Past missions

The first successful fly-by mission to Mars was NASA's Mariner 4, launched in 1964. The first successful objects to land on the surface were two Soviet probes, Mars 2 and Mars 3 from the Mars probe program, launched in 1971, but both lost contact within seconds of landing. Then came the 1975 NASA launches of the Viking program, which consisted of two orbiters, each having a lander; both landers successfully touched down in 1976. Viking 1 remained operational for six years, Viking 2 for three. The Viking landers relayed the first color pictures of Mars[69] and also mapped the surface of Mars so well that the images are still sometimes used to this day. Mariner 4 (Mariner-Mars 1964) was the fourth in a series of spacecraft used for planetary exploration in a flyby mode and performed the first successful flyby of the planet Mars, returning the first pictures of the Martian surface. ... CCCP redirects here. ... The Mars program was a series of Mars unmanned landers and orbiters launched by the Soviet Union in the early 1970s. ... It has been suggested that this article or section be merged with Mars 2. ... The Mars program was a series of Mars unmanned landers and orbiters launched by the Soviet Union in the early 1970s. ... Viking mission profile. ... Viking 1 was the first of two spacecraft sent to Mars as part of NASAs Viking program, and holds the record for the longest Mars surface mission of 4 years and 28 days (from landing until mission termination). ... Frost on Mars. ...


The Soviet probes Phobos 1 and 2 were sent to Mars in 1988 to study Mars and its two moons. Phobos 1 lost contact on the way to Mars. Phobos 2, while successfully photographing Mars and Phobos, failed just before it was set to release two landers on Phobos's surface. Illustration of the Phobos spacecraft Image of Phobos taken by Phobos 2 spacecraft The Phobos program was an unmanned space mission consisting of two probes launched by the Soviet Union to study Mars and its moons Phobos and Deimos. ...


Following the 1992 failure of the Mars Observer orbiter, NASA launched the Mars Global Surveyor in 1996. This mission was a complete success, having finished its primary mapping mission in early 2001. Contact was lost with the probe in November 2006 during its third extended program, spending exactly 10 operational years in space. Only a month after the launch of the Surveyor, NASA launched the Mars Pathfinder, carrying a robotic exploration vehicle Sojourner, which landed in the Ares Vallis on Mars. This mission was also successful, and received much publicity, partially due to the many images that were sent back to Earth.[70] An artists concept of the Mars Observer in orbit around Mars. ... The Mars Global Surveyor (MGS) was a US spacecraft developed by NASA and the Jet Propulsion Laboratory and launched November 1996. ... The Mars Pathfinder was launched on December 4, 1996 by NASA aboard a Delta II just a month after the Mars Global Surveyor was launched. ... Sojourner next to the rock Barnacle Bill The Sojourner rover was the first space exploration rover to successfully reach another planet. ... Ares Vallis is a valley on Mars which appears to have been carved by fluids, perhaps water. ...


Current missions

Spirit's lander on Mars
Spirit's lander on Mars

In 2001 NASA launched the successful Mars Odyssey orbiter, which is still in orbit as of March 2008, and the ending date has been extended to September 2008. Odyssey's Gamma Ray Spectrometer detected significant amounts of hydrogen in the upper metre or so of Mars's regolith. This hydrogen is thought to be contained in large deposits of water ice.[71] Image File history File links Download high resolution version (1024x722, 158 KB) Popis Mars Exploration Rover Spirit took this mosaic on 16th sol. ... Image File history File links Download high resolution version (1024x722, 158 KB) Popis Mars Exploration Rover Spirit took this mosaic on 16th sol. ... The launch patch for Spirit, featuring Marvin the Martian. ... Artists concept of the 2001 Mars Odyssey Spacecraft 2001 Mars Odyssey is an unmanned spacecraft orbiting the planet Mars. ... Source of image data: Los Alamos National Laboratory The Gamma Ray Spectrometer (GRS) uses the gamma-ray part of the spectrum to look for the presence of 20 elements from the periodic table, and is used in the exploration of Mars. ... Regolith (Greek: blanket rock) is a layer of loose, heterogeneous material covering solid rock. ...


In 2003, the ESA launched the Mars Express craft, consisting of the Mars Express Orbiter and the lander Beagle 2. Beagle 2 failed during descent and was declared lost in early February 2004.[72] In early 2004 the Planetary Fourier Spectrometer team announced it had detected methane in the Martian atmosphere. ESA announced in June 2006 the discovery of aurorae on Mars.[73] ESA redirects here. ... Oblique view of the Reull Vallis near the Hellas basin, rendered from data obtained by the Mars Express orbiters High Resolution Stereo Camera (HRSC) The Mars Express Orbiter is part of the Mars Express program, a European Space Agency (ESA) mission to Mars. ... Beagle 2 was an unsuccessful British landing spacecraft that formed part of the European Space Agencys 2003 Mars Express mission. ... An image of the interferometer used in the core of the Planetary Fourier Spectrometer. ... The Aurora Borealis, or Northern Lights, shines above Bear Lake Aurora Borealis as seen over Canada at 11,000m (36,000 feet) Red and green Aurora in Fairbanks, Alaska Aurora Borealis redirects here. ...


Also in 2003, NASA launched the twin Mars Exploration Rovers named Spirit (MER-A) and Opportunity (MER-B). Both missions landed successfully in January 2004 and have met or exceeded all their targets. Among the most significant scientific returns has been conclusive evidence that liquid water existed at some time in the past at both landing sites. Martian dust devils and windstorms have occasionally cleaned both rovers' solar panels, and thus increased their lifespan.[74] Artists Concept of Rover on Mars NASAs Mars Exploration Rover (MER) Mission (since 2003) is a unmanned Mars exploration mission that includes sending two Rovers (robots) to explore the Martian surface and geology. ... The launch patch for Spirit, featuring Marvin the Martian. ... The launch patch for Opportunity, featuring Duck Dodgers (Daffy Duck). ... For other uses of this phrase, see Dust devil (disambiguation). ...


On August 12, 2005 the NASA Mars Reconnaissance Orbiter probe was launched toward the planet, arriving in orbit on March 10, 2006 to conduct a two-year science survey. The orbiter will map the Martian terrain and weather to find suitable landing sites for upcoming lander missions. It also contains an improved telecommunications link to Earth, with more bandwidth than all previous missions combined. is the 224th day of the year (225th in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... NASAs Mars Reconnaissance Orbiter (MRO) is a multipurpose spacecraft designed to conduct reconnaissance and exploration of Mars from orbit. ... is the 69th day of the year (70th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ...


The Mars Reconnaissance Orbiter snapped the first image of a series of active avalanches near the planet's north pole, scientists said March 3, 2008.[75] NASAs Mars Reconnaissance Orbiter (MRO) is a multipurpose spacecraft designed to conduct reconnaissance and exploration of Mars from orbit. ... A Himalayan avalanche near Mount Everest. ... For other uses, see North Pole (disambiguation). ... is the 62nd day of the year (63rd in leap years) in the Gregorian calendar. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance with the Gregorian calendar. ...

A prototype of the Phoenix lander practices robotic arm control at a test site in Death Valley.
A prototype of the Phoenix lander practices robotic arm control at a test site in Death Valley.

The most recent mission to Mars is the NASA Phoenix Mars lander, which launched August 4, 2007 and arrived on the north polar region of Mars on May 25, 2008[76]. The lander has a robotic arm with a 2.5 m reach and capable of digging a meter into the Martian soil. The lander will be in an area with an 80% chance of ice being less than 30 cm below the surface, and has a microscopic camera capable of resolving to one-thousandth the width of a human hair.[77] Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... This article is about the Mars lander. ... For other uses, see Death Valley (disambiguation). ... This article is about the Mars lander. ... is the 216th day of the year (217th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 145th day of the year (146th in leap years) in the Gregorian calendar. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance with the Gregorian calendar. ...


The Dawn spacecraft will fly by Mars in February 2009 for a gravity assist on its way to investigate Vesta and then Ceres. The Dawn Mission is a NASA mission that will send the Dawn spacecraft, a robotic space probe, to the asteroid belt. ... 4 Vesta (ves-ta) is the second most massive asteroid in the asteroid belt, with a mean diameter of about 530 km and an estimated mass 12% the mass of the entire asteroid belt. ... Spectral type: G[8] Absolute magnitude: 3. ...


Future missions

Phoenix will be followed by the Mars Science Laboratory in 2009, a bigger, faster (90 m/h), and smarter version of the Mars Exploration Rovers. Experiments include a laser chemical sample that can deduce the make-up of rocks at a distance of 13 m.[78] 2007 Mars Science Laboratory concept Schematic diagram of the planned rover components The Mars Science Laboratory (or MSL for short) is a NASA rover scheduled to launch in September 2009 and perform a precision landing on Mars in July-September 2010. ...


The joint Russian and Chinese Phobos-Grunt sample-return mission, to return samples of Mars's moon Phobos, is scheduled for a 2009 launch. In 2013 the ESA plans to launch its first Rover to Mars, the ExoMars rover will be capable of drilling 2 m into the soil in search of organic molecules.[79][80] Phobos-Grunt (rus. ... ExoMars model at ILA 2006 (Berlin) ExoMars. ...


The Finnish-Russian MetNet mission will consist of sending tens of small landers on the Martian surface in order to establish a wide-spread surface observation network to investigate the planet's atmospheric structure, physics and meteorology.[81] A precursor mission using 1-2 landers is scheduled for launch in 2009 or 2011[citation needed]. One possibility is a piggyback launch on the Russian Phobos Grunt mission.[82] Other launches will take place in the launch windows extending to 2019. Phobos-Grunt (rus. ...


Manned Mars exploration by the United States has been explicitly identified as a long-term goal in the Vision for Space Exploration announced in 2004 by US President George W. Bush.[83] NASA and Lockheed Martin have begun work on the Orion spacecraft, formerly the Crew Exploration Vehicle, which is currently scheduled to send a human expedition to Earth's moon by 2020 as a stepping stone to an expedition to Mars thereafter. Artists conception of a human mission on the surface of Mars A human mission to Mars (sometimes, manned mission to Mars) refers to humans going to the planet Mars, including orbiting Mars, landing on the surface, or walking on the surface. ... Image from NASA site Two planned configurations for a return to the moon, heavy lift (left) and crew (right) The Vision for Space Exploration is the United States space policy announced on January 14, 2004 by President George W. Bush. ... George Walker Bush (born July 6, 1946) is the forty-third and current President of the United States of America, originally inaugurated on January 20, 2001. ... Lockheed/BAE/Northrop F-35 Lockheed Trident missile C-130 Hercules; in production since the 1950s, now as the C-130J Lockheed Martin (NYSE: LMT) is an aerospace manufacturer formed in 1995 by the merger of Lockheed Corporation with Martin Marietta. ... Orion is a spacecraft currently under development by the United States National Aeronautics and Space Administration (NASA). ...


The European Space Agency hopes to land humans on Mars between 2030 and 2035.[84] This will be preceded by successively larger probes, starting with the launch of the ExoMars probe and a Mars Sample Return Mission. ExoMars model at ILA 2006 (Berlin) ExoMars. ...


On September 28, 2007, NASA administrator Michael D. Griffin stated that NASA aims to put a man on Mars by 2037: in 2057, we should be celebrating 20 years of man on Mars.[85] is the 271st day of the year (272nd in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... For other people with the same name, see Michael Griffin (disambiguation). ...


Astronomy on Mars

Main article: Astronomy on Mars
Photograph of a Martian sunset taken by Spirit at Gusev crater, May 19, 2005.
Photograph of a Martian sunset taken by Spirit at Gusev crater, May 19, 2005.

With the existence of various orbiters, landers, and rovers, it is now possible to study astronomy from the Martian skies. The Earth and the Moon are easily visible while Mars’ moon Phobos appears about one third the angular diameter of the full Moon as it appears from Earth. On the other hand Deimos appears more or less star-like, and appears only slightly brighter than Venus does from Earth.[86] This article presents information and images about viewing astronomical phenomena from the planet Mars. ... ImageMetadata File history File links Download high resolution version (2352x713, 56 KB) Popis Cut from Image:MarsSunset. ... ImageMetadata File history File links Download high resolution version (2352x713, 56 KB) Popis Cut from Image:MarsSunset. ... Gusev Crater is a meteor crater in Russia. ... is the 139th day of the year (140th in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... For other uses, see Astronomy (disambiguation). ... The angular diameter of an object as seen from a given position is the diameter measured as an angle. ...


There are also various phenomena well-known on Earth that have now been observed on Mars, such as meteors and auroras.[73] A transit of the Earth as seen from Mars will occur on November 10, 2084. There are also transits of Mercury and transits of Venus, and the moon Deimos is of sufficiently small angular diameter that its partial "eclipses" of the Sun are best considered transits (see Transit of Deimos from Mars). Photo of a burst of meteors with extended exposure time A meteor is the visible path of a meteoroid that enters the Earths (or another bodys) atmosphere, commonly called a shooting star or falling star. ... Aurora borealis Aurora borealis The aurora is a glow observed in the night sky, usually in the polar zone. ... Earth and Moon transiting the Sun in 2084, as seen from Mars Earth and Moon from Mars, as imaged by Mars Global Surveyor A transit of Earth across the Sun as seen from Mars takes place when the planet Earth passes directly between the Sun and Mars, obscuring a small... is the 314th day of the year (315th in leap years) in the Gregorian calendar. ... (Redirected from 2084) (20th century - 21st century - 22nd century - other centuries) Definition In calendars based on the Christian Era or Common Era, such as the Gregorian calendar, the 21st century is the current century, as of this writing, lasting from 2000-2099. ... A transit of Mercury across the Sun as seen from Mars takes place when the planet Mercury passes directly between the Sun and Mars, obscuring a small part of the Suns disc for an observer on Mars. ... A transit of Venus across the Sun as seen from Mars takes place when the planet Venus passes directly between the Sun and Mars, obscuring a small part of the Suns disc for an observer on Mars. ... Deimos transits the Sun, as seen by Mars Rover Opportunity on March 4, 2004 A transit of Deimos across the Sun as seen from Mars takes place when Deimos passes directly between the Sun and a point on the surface of Mars, obscuring a small part of the Suns...


Viewing

To the naked-eye, Mars usually appears a distinct yellow, orange, or reddish color, and varies in brightness more than any other planet as seen from Earth over the course of its orbit. The apparent magnitude of Mars varies from +1.8 at conjunction to as high as -2.9 at perihelic opposition.[3] When farthest away from the Earth, it is more than seven times as far from the latter as when it is closest. When least favourably positioned, it can be lost in the Sun's glare for months at a time. At its most favourable times—which occur twice every 32 years, alternately at 15 and 17-year intervals, and always between late July and late September—Mars shows a wealth of surface detail to a telescope. Especially noticeable, even at low magnification, are the polar ice caps.[87] The apparent magnitude (m) of a star, planet or other celestial body is a measure of its apparent brightness as seen by an observer on Earth. ... A diagram of Keplerian orbital elements. ... Opposition is a term used in positional astronomy and astrology to indicate when one celestial body is on the opposite side of the sky when viewed from a particular place (usually the Earth). ... This article does not cite any references or sources. ... This article is about polar ice caps in general. ...


The point of Mars’ closest approach to the Earth is known as opposition. The length of time between successive oppositions, or the synodic period, is 780 days. Because of the eccentricities of the orbits, the times of opposition and minimum distance can differ by up to 8.5 days. The minimum distance varies between about 55 and 100 million km due to the planets' elliptical orbits.[3] The next Mars opposition will occur on January 29, 2010. The orbital period is the time it takes a planet (or another object) to make one full orbit. ... Elliptical redirects here. ... is the 29th day of the year in the Gregorian calendar. ... 2010 (MMX) will be a common year starting on Friday of the Gregorian calendar. ...


As Mars approaches opposition it begins a period of retrograde motion, which means it will appear to move backwards in a looping motion with respect to the background stars. This article is about retrograde motion. ...


2003 closest approach

The rotation of Mars as seen in a small telescope in 2003.
The rotation of Mars as seen in a small telescope in 2003.
Mars oppositions from 2003-2018, viewed from above the ecliptic with the Earth centered.
Mars oppositions from 2003-2018, viewed from above the ecliptic with the Earth centered.

On August 27, 2003, at 9:51:13 UT, Mars made its closest approach to Earth in nearly 60,000 years: 55,758,006 km. This occurred when Mars was one day from opposition and about three days from its perihelion, making Mars particularly easy to see from Earth. The last time it came so close is estimated to have been on September 12, 57,617 BC, the next time being in 2287. However, this record approach was only very slightly closer than other recent close approaches. For instance, the minimum distance on August 22, 1924 was 0.37284 AU, compared with 0.37271 AU on August 27, 2003, and the minimum distance on August 24, 2208 will be 0.37278 AU.[88] The orbital changes of Earth and Mars are making the approaches nearer: the 2003 record will be bettered 22 times by the year 4000. Mars images from earth in 2004 This animation was constructed by actual photographs I made of Mars through my telescope (6 reflector) from Aug 3 to Sep 5, 2004. ... Mars images from earth in 2004 This animation was constructed by actual photographs I made of Mars through my telescope (6 reflector) from Aug 3 to Sep 5, 2004. ... is the 239th day of the year (240th in leap years) in the Gregorian calendar. ... Year 2003 (MMIII) was a common year starting on Wednesday of the Gregorian calendar. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ... is the 255th day of the year (256th in leap years) in the Gregorian calendar. ... The Middle Paleolithic (or Middle Palaeolithic) is the second subdivision of the Paleolithic or Old Stone Age as it is understood in Europe, Africa and Asia. ... is the 234th day of the year (235th in leap years) in the Gregorian calendar. ... For the rap album, see 1924 (album). ... The astronomical unit (AU or au or a. ... is the 239th day of the year (240th in leap years) in the Gregorian calendar. ... Year 2003 (MMIII) was a common year starting on Wednesday of the Gregorian calendar. ... is the 236th day of the year (237th in leap years) in the Gregorian calendar. ... In Futurama, Scientists increase the speed of light during this year. ...


Historical observations

The history of observations of Mars is marked by the oppositions of Mars, when the planet is closest to Earth and hence is most easily visible, which occur every couple of years. Even more notable are the perihelic oppositions of Mars which occur about every 15–17 years, and are distinguished because Mars is close to perihelion, making it even closer to Earth. Aristotle was among the first known writers to describe observations of Mars, noting that, as it passed behind the Moon, it was farther away than was originally believed. For other uses, see Aristotle (disambiguation). ...


The only occultation of Mars by Venus observed was that of October 3, 1590, seen by M. Möstlin at Heidelberg.[89] In this July, 1997 still frame captured from video, the bright star Aldebaran has just reappeared on the dark limb of the waning crescent moon in this predawn occultation. ... is the 276th day of the year (277th in leap years) in the Gregorian calendar. ... Bold text{| align=right cellpadding=3 id=toc style=margin-left: 15px; |- | align=center colspan=2 | Years: 1587 1588 1589 - 1590 - 1591 1592 1593 |-vdsf gno[gldw[pvkijxaiamknn csogfhbvdowkhbfkqhjkhrjkhwgfhbjkpnkfokfgok3pkpk9pjhkt9erktyujkip9kijker9thhrkg9hkitr9gtkih9t0ykltk[u0jo0iey9uhyit90ertyhige9rity9riyh9ujirtyuhjnh-4e9tyigh9thiuy0h8tyh34tu8uy8u8u8u8rtu5y8ru8thu0tru0ut0rhutuh0trhu0hseogtrhr8uyhju8t89er9te9r8fy8shit ass dick bitch fuck | align=center colspan=2 | Decades: 1560s 1570s 1580s - 1590s - 1600s 1610s 1620s |- | align=center | Centuries... Michael Maestlin (1550-1631) was a German astronomer and mathematician. ... For other uses, see Heidelberg (disambiguation). ...


In 1609, Mars was viewed by Galileo, who was first to see it via telescope.

Map of Mars by Giovanni Schiaparelli.
Map of Mars by Giovanni Schiaparelli.

By the 19th century, the resolution of telescopes reached a level sufficient for surface features to be identified. In September 1877, a perihelic opposition of Mars occurred on September 5. In that year, Italian astronomer Giovanni Schiaparelli, then in Milan, used a 22 cm telescope to help produce the first detailed map of Mars. These maps notably contained features he called canali, which were later shown to be an optical illusion. These canali were supposedly long straight lines on the surface of Mars to which he gave names of famous rivers on Earth. His term was popularly mistranslated as canals.[90] Image File history File links Karte_Mars_Schiaparelli_MKL1888. ... Image File history File links Karte_Mars_Schiaparelli_MKL1888. ... is the 248th day of the year (249th in leap years) in the Gregorian calendar. ... Giovanni Virginio Schiaparelli (March 14, 1835 – July 4, 1910) was an Italian astronomer. ... For other uses, see Milan (disambiguation). ... An optical illusion. ...

Mars sketched as observed by Lowell sometime before 1914. (South top)
Mars sketched as observed by Lowell sometime before 1914. (South top)

Influenced by the observations the orientalist Percival Lowell founded an observatory which had a 300 and 450 mm telescope. The observatory was used for the exploration of Mars during the last good opportunity in 1894 and the following less favorable oppositions. He published several books on Mars and life on the planet, which had a great influence on the public. The canali were also found by other astronomers, like Henri Joseph Perrotin and Louis Thollon in Nice, using one of the largest telescopes of that time. Percival Lowell (March 13, 1855 – November 12, 1916) was an author, mathematician, and esteemed astronomer who fueled speculation that there were canals on Mars, founded the Lowell Observatory in Flagstaff, Arizona, and formed the beginning of the work and theories that led to the discovery of Pluto 14 years after... Lowell Observatory Percival observing Mars from the Clark telescope at the Lowell Observatory. ... Henri Joseph Anastase Perrotin (December 19, 1845 – February 29, 1904) was a French astronomer. ... This article is about the French city. ...


The seasonal changes (consisting of the diminishing of the polar caps and the dark areas formed during Martian summer) in combination with the canals lead to speculation about life on Mars, and it was a long held belief that Mars contained vast seas and vegetation. The telescope never reached the resolution required to give proof to any speculations. However, as bigger telescopes were used, fewer long, straight canali were observed. During an observation in 1909 by Flammarion with a 840 mm telescope, irregular patterns were observed, but no canali were seen.[91] Camille Flammarion Camille Flammarion (February 26, 1842 – June 3, 1925) was a French astronomer and author. ...

Map of Mars from Hubble Space Telescope as seen near the 1999 opposition. (North top)
Map of Mars from Hubble Space Telescope as seen near the 1999 opposition. (North top)

Even in the 1960s articles were published on Martian biology, putting aside explanations other than life for the seasonal changes on Mars. Detailed scenarios for the metabolism and chemical cycles for a functional ecosystem have been published.[92] The Hubble Space Telescope (HST; also known colloquially as the Hubble or just Hubble) is a space telescope that was carried into Earth orbit by the Space Shuttle in April 1990. ...


It was not until spacecraft visited the planet during NASA's Mariner missions in the 1960s that these myths were dispelled. The results of the Viking life-detection experiments started an intermission in which the hypothesis of a hostile, dead planet was generally accepted. The Space Shuttle Discovery as seen from the International Space Station. ... Launch of Mariner 1 (NASA) The Mariner program was a program conducted by the American space agency NASA that launched a series of robotic interplanetary probes designed to investigate Mars, Venus and Mercury. ...


Some maps of Mars were made using the data from these missions, but it was not until the Mars Global Surveyor mission, launched in 1996 and operated until late 2006, that complete, extremely detailed maps were obtained. These maps are now available online.[93] The Mars Global Surveyor (MGS) was a US spacecraft developed by NASA and the Jet Propulsion Laboratory and launched November 1996. ...


Mars in culture

Historical connections

Mars is named after the Roman god of war. In Babylonian astronomy, the planet was named after Nergal, their deity of fire, war, and destruction, most likely due to the planet's reddish appearance.[94] When the Greeks equated Nergal with their god of war, Ares, they named the planet Ἄρεως ἀστἡρ (Areos aster), or "star of Ares". Then, following the identification of Ares and Mars, it was translated into Latin as stella Martis, or "star of Mars", or simply Mars. The Greeks also called the planet Πυρόεις Pyroeis meaning "fiery". In Hindu mythology, Mars is known as Mangala (मंगल). The planet is also called Angaraka in Sanskrit, after the celibate god of war, who possesses the signs of Aries and Scorpio, and teaches the occult sciences. The planet was known by the Egyptians as "Ḥr Dšr";;;; or "Horus the Red". The Hebrews named it Ma'adim (מאדים)—"the one who blushes"; this is where one of the largest canyons on Mars, the Ma'adim Vallis, gets its name. It is known as al-Mirrikh in Arabic, and Merih in Turkish. In Urdu and Persian it is written as مریخ and known as "Merikh". The etymology of al-Mirrikh is unknown. Ancient Persians named it Bahram, the Zoroastrian god of faith and it is written as بهرام. Ancient Turks called it Sakit. The Chinese, Japanese, Korean and Vietnamese cultures refer to the planet as 火星, or the fire star, a name based on the ancient Chinese mythological cycle of Five elements. Ancient Rome was a civilization that grew from a small agricultural community founded on the Italian Peninsula circa the 9th century BC to a massive empire straddling the Mediterranean Sea. ... Mars, painting by Diego Velazquez Mars was the Roman warrior god, the son of Juno and Jupiter, husband of Bellona, and the lover of Venus. ... Babylonia was a state in southern Mesopotamia, in modern Iraq, combining the territories of Sumer and Akkad. ... For other uses, see Nergal (disambiguation). ... See also: List of deities Look up deity in Wiktionary, the free dictionary. ... Hindu mythology is a term used by modern scholarship for a large body of Indian literature that details the lives and times of legendary personalities, deities and divine incarnations on earth interspersed with often large sections of philosophical and ethical discourse. ... In Jyotish astrology, Mangala is the name for Mars, the red planet. ... Sanskrit ( , for short ) is a classical language of India, a liturgical language of Hinduism, Buddhism, Sikhism, and Jainism, and one of the 23 official languages of India. ... Celibacy may refer either to being unmarried or to sexual abstinence. ... Aries, the ram, is the first astrological sign of the zodiac and its origins are from the Aries constellation. ... Scorpio may refer to: The scorpion, a venomous animal, from which most of the following get their name The Scorpius constellation, one of the constellations of the western zodiac Scorpio (astrology), the astrological sign represented by this constellation Scorpio (Dart-thrower), Roman artillery invented in 50 BC. The Scorpio ROV... Ihy redirects here. ... This article is about the Hebrew people. ... Grand Canyon, Arizona A canyon, or gorge, is a valley walled by cliffs. ... Maadim Vallis is one of the largest canyons on Mars, about 700 kilometers long and significantly larger than Earths Grand Canyon. ... Urdu ( , , trans. ... Look up Persian in Wiktionary, the free dictionary. ... Chinese Wood (木) | Fire (火) Earth (土) | Metal (金) | Water (æ°´) Japanese Earth (地) | Water (æ°´) | Fire (火) | Air / Wind (風) | Void / Sky / Heaven (空) Hinduism and Buddhism Vayu / Pavan — Air / Wind Agni / Tejas — Fire Akasha — Aether Prithvi / Bhumi — Earth Ap / Jala — Water In traditional Chinese philosophy, natural phenomena can be classified into the Five Elements (Chinese: ; Pinyin: ): wood, fire...

Its symbol, derived from the astrological symbol of Mars, is a circle with a small arrow pointing out from behind. It is a stylized representation of a shield and spear used by the Roman God Mars. Mars in Roman mythology was the God of War and patron of warriors. This symbol is also used in biology to describe the male sex, and in alchemy to symbolise the element iron which was considered to be dominated by Mars whose characteristic red colour is coincidentally due to iron oxide.[95] ♂ occupies Unicode position U+2642. Image File history File links Mars_symbol. ... ... For other uses, see Alchemy (disambiguation). ... The Unicode Standard, Version 5. ...

Intelligent "Martians"

An 1893 soap ad playing on the popular idea that Mars was populated.
An 1893 soap ad playing on the popular idea that Mars was populated.

The popular idea that Mars was populated by intelligent Martians exploded in the late 19th century. Schiaparelli's "canali" observations combined with Percival Lowell's books on the subject put forward the standard notion of a planet that was a drying, cooling, dying world with ancient civilizations constructing irrigation works.[96] Image File history File linksMetadata Size of this preview: 498 × 599 pixelsFull resolution (713 × 858 pixel, file size: 117 KB, MIME type: image/jpeg) 1893 ad from a Chicago newspaper for “Kirk’s Soap”. The ad plays on the opening that year of the Yerkes Observatories 1-meter (40-inch... Image File history File linksMetadata Size of this preview: 498 × 599 pixelsFull resolution (713 × 858 pixel, file size: 117 KB, MIME type: image/jpeg) 1893 ad from a Chicago newspaper for “Kirk’s Soap”. The ad plays on the opening that year of the Yerkes Observatories 1-meter (40-inch... This article is about hypothetical native inhabitants of the planet Mars. ... Giovanni Virginio Schiaparelli (March 14, 1835 – July 4, 1910) was an Italian astronomer. ... Percival Lowell (March 13, 1855 – November 12, 1916) was an author, mathematician, and esteemed astronomer who fueled speculation that there were canals on Mars, founded the Lowell Observatory in Flagstaff, Arizona, and formed the beginning of the work and theories that led to the discovery of Pluto 14 years after...


Many other observations and proclamations by notable personalities added to what has been termed "Mars Fever".[97] In 1899 while investigating atmospheric radio noise using his receivers in his Colorado Springs lab, inventor Nikola Tesla observed repetitive signals that he later surmised might have been radio communications coming from another planet, possibly Mars. In a 1901 interview Tesla said: Nikola Tesla (Nih koh la TESS lah) [2](Serbian Cyrillic: ) (10 July 1856 – 7 January 1943) was an inventor, physicist, mechanical and electrical engineer. ...

It was some time afterward when the thought flashed upon my mind that the disturbances I had observed might be due to an intelligent control. Although I could not decipher their meaning, it was impossible for me to think of them as having been entirely accidental. The feeling is constantly growing on me that I had been the first to hear the greeting of one planet to another.[98]

Tesla's theories gained support from Lord Kelvin who, while visiting the United States in 1902, was reported to have said that he thought Tesla had picked up Martian signals being sent to the United States.[99] However, Kelvin "emphatically" denied this report shortly before departing America: "What I really said was that the inhabitants of Mars, if there are any, were doubtless able to see New York, particularly the glare of the electricity."[100] For other persons named William Thomson, see William Thomson (disambiguation). ...


In a New York Times article in 1901, Edward Charles Pickering, director of the Harvard College Observatory, said that they had received a telegram from Lowell Observatory in Arizona that seemed to confirm that Mars was trying to communicate with the Earth.[101] The New York Times is a daily newspaper published in New York City and distributed internationally. ... Edward Charles Pickering (July 19, 1846 – February 3, 1919) was an American astronomer and physicist, brother of William Henry Pickering. ... Harvard College Observatory, about 1900. ... Lowell Observatory Percival observing Mars from the Clark telescope at the Lowell Observatory. ... Official language(s) English Spoken language(s) English 74. ...

Early in December of 1900, we received from Lowell Observatory in Arizona a telegram that a shaft of light had been seen to project from Mars (the Lowell observatory makes a specialty of Mars) lasting seventy minutes. I wired these facts to Europe and sent out neostyle copies through this country. The observer there is a careful, reliable man and there is no reason to doubt that the light existed. It was given as from a well-known geographical point on Mars. That was all. Now the story has gone the world over. In Europe it is stated that I have been in communication with Mars, and all sorts of exaggerations have spring up. Whatever the light was, we have no means of knowing. Whether it had intelligence or not, no one can say. It is absolutely inexplicable.[101]

Pickering later proposed creating a set of mirrors in Texas with the intention of signaling Martians. For other uses, see Texas (disambiguation). ...


It should be noted that pulsars (more properly neutron stars) emit electromagnetic radiation, usually low frequency waves, such as radio waves. They do this quite regularly, up to such a point that some observatories use them as clocks. Nikola Tesla may not have witnessed a message from aliens because he only had one reading from a single telescope (the problem with this is that it only determines the direction of the signal. To determine the position in three dimension, two observers are needed. Since fields of radio telescopes did not exist in his time and he did not notice until after, it is highly unlikely he observed the radio signals from two different locations).


In fiction

Main article: Mars in fiction

The depiction of Mars in fiction has been stimulated by its dramatic red color and by early scientific speculations that its surface conditions not only might support life, but intelligent life. Fictional representations of Mars have been popular for over a century. ...

Alien tripod illustration from the 1906 French edition of H.G. Wells' The War of the Worlds.
Alien tripod illustration from the 1906 French edition of H.G. Wells' The War of the Worlds.

Thus originated a large number of science fiction scenarios, the best known of which is H. G. Wells' The War of the Worlds, in which Martians seek to escape their dying planet by invading Earth. A subsequent radio version of The War of the Worlds on October 30, 1938 was presented as a live news broadcast, and many listeners mistook it for the truth.[102] Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Science fiction is a form of speculative fiction principally dealing with the impact of imagined science and technology, or both, upon society and persons as individuals. ... Herbert George Wells (September 21, 1866 – August 13, 1946), better known as H. G. Wells, was an English writer best known for such science fiction novels as The Time Machine, The War of the Worlds, The Invisible Man, The First Men in the Moon and The Island of Doctor Moreau. ... The War of the Worlds (1898), by H. G. Wells, is an early science fiction novel (or novella) which describes an invasion of England by aliens from Mars. ... For other uses, see The War of the Worlds (disambiguation). ... is the 303rd day of the year (304th in leap years) in the Gregorian calendar. ... Year 1938 (MCMXXXVIII) was a common year starting on Saturday (link will display the full calendar) of the Gregorian calendar. ... For other uses, see The War of the Worlds (disambiguation). ...


Also influential were Ray Bradbury's The Martian Chronicles, in which human explorers accidentally destroy a Martian civilization, Edgar Rice Burroughs' Barsoom series and a number of Robert A. Heinlein stories before the mid-sixties. The Martian Chronicles is a 1950 science fiction novel by Ray Bradbury that chronicles the colonization of Mars by humans fleeing from a troubled Earth, and the conflict between aboriginal Martians and the new colonists. ... Edgar Rice Burroughs Edgar Rice Burroughs (September 1, 1875 – March 19, 1950) was an American author, best known for his creation of the jungle hero Tarzan, although he also produced works in many genres. ... A Princess of Mars by Edgar Rice Burroughs, McClurg, 1917 Barsoom is a fictional version of the planet Mars invented by author Edgar Rice Burroughs for a series of action adventure stories. ... Robert Anson Heinlein (July 7, 1907 – May 8, 1988) was one of the most popular, influential, and controversial authors of hard science fiction. ...


Author Jonathan Swift made reference to the moons of Mars, about 150 years before their actual discovery by Asaph Hall, detailing reasonably accurate descriptions of their orbits, in the 19th chapter of his novel Gulliver's Travels.[103] Jonathan Swift Jonathan Swift (November 30, 1667 – October 19, 1745) was an Irish cleric, satirist, essayist, political pamphleteer (first for Whigs then for Tories), and poet, famous for works like Gullivers Travels, A Modest Proposal, A Journal to Stella, The Drapiers Letters, The Battle of the Books, and... Asaph Hall (October 15, 1829 – November 22, 1907) was an American astronomer who is most famous for having discovered the moons of Mars (namely Deimos and Phobos) in 1877. ... For other uses, see Gullivers Travels (disambiguation). ...


After the Mariner and Viking spacecraft had returned pictures of Mars as it really is, an apparently lifeless and canal-less world, these ideas about Mars had to be abandoned and a vogue for accurate, realist depictions of human colonies on Mars developed, the best known of which may be Kim Stanley Robinson's Mars trilogy. However, pseudo-scientific speculations about the Face on Mars and other enigmatic landmarks spotted by space probes have meant that ancient civilizations continue to be a popular theme in science fiction, especially in film.[104] Launch of Mariner 1 (NASA) The Mariner program was a program conducted by the American space agency NASA that launched a series of robotic interplanetary probes designed to investigate Mars, Venus and Mercury. ... Viking mission profile. ... For the late American actress, see Kim Stanley. ... The Mars trilogy is a series of award-winning science fiction novels by Kim Stanley Robinson, chronicling the settlement and terraforming of the planet Mars. ... Mars Orbital Cameras 2001 image of the face The Face on Mars is a large feature on the surface of the planet Mars located in the Cydonia region, thought by many to resemble a human face. ... Italic textBold text Technicians work on the Ulysses space probe. ...


Another popular theme, particularly among American writers, is the Martian colony that fights for independence from Earth. This is a major plot element in the novels of Greg Bear and Kim Stanley Robinson, as well as the movie Total Recall (based on a short story by Philip K. Dick) and the television series Babylon 5. Many video games also use this element, including Red Faction and the Zone of the Enders series. Mars (and its moons) were also the setting for the popular Doom video game franchise and the later Martian Gothic. Gregory Dale Bear (born August 20, 1951) is a science fiction author. ... For the late American actress, see Kim Stanley. ... Total Recall is an American science fiction film released on June 1, 1990 starring Arnold Schwarzenegger, directed by Paul Verhoeven and written by Ronald Shusett, Dan OBannon, Jon Povill and Gary Goldman. ... Philip Kindred Dick (December 16, 1928 – March 2, 1982) was an American writer, mostly known for his works of science fiction. ... Babylon 5 is an epic American science fiction television series created, produced, and largely written by J. Michael Straczynski. ... For the single Red Fraction by Mell, see Red Fraction. ... Zone of the Enders, also known as Z.O.E., is a video game that was developed and published by Konami in 2001 for the PlayStation 2. ... Doom (or DOOM)[1] is a 1993 computer game by id Software that is a landmark title in the first-person shooter genre. ...


In music

In Gustav Holst's The Planets, Mars is depicted as the "Bringer of War". Gustav Holst Gustav Holst (September 21, 1874, Cheltenham, Gloucestershire - May 25, 1934, London) [1] [2] was an English composer and was a music teacher for over 20 years. ... This page is about the orchestral suite by Gustav Holst. ...


See also

Mars Portal
Solar System Portal

Image File history File links Mars_Hubble. ... Image File history File links Download high resolution version (1024x1274, 113 KB) Original caption released with image This is a montage of planetary images taken by spacecraft managed by the Jet Propulsion Laboratory in Pasadena, CA. Included are (from top to bottom) images of Mercury, Venus, Earth (and Moon), Mars... Mars Mars is the focus of much speculation and serious study about possible human colonization. ... The Darian Calendar is a system of time-keeping designed to serve the needs of any possible future human settlers on the planet Mars. ... Green people redirects here. ... Artificial objects on Mars that are currently in use are the MER-A Spirit rover and the MER-B Opportunity rover. ... What follows is a list of chasmata on Mars. ... There are hundreds of thousands of craters on Mars, but only some of them have names. ... Valles (singular vallis) on Mars are similar to valleys on Earth. ... Artists conception of the process of terraforming Mars Since the origin of the idea of terraforming, or changing a planets environment to produce a world that is habitable by humans, one of the primary subjects of study for potential terraforming has been the planet Mars. ...

Notes

  1. ^ Best fit ellipsoid
  2. ^ There are many serpentinization reactions. Olivine is a solid solution between forsterite and fayalite whose general formula is (Fe,Mg)2SiO4. The reaction producing methane from olivine can be written (in balanced form) as: Forsterite + Fayalite + Water + Carbonic acid → Serpentine + Magnetite + Methane , or: 18Mg2SiO4 + 6Fe2SiO4 + 26H2O + CO212Mg3Si2O5(OH)4 + 4Fe3O4 + CH4

3D rendering of an ellipsoid In mathematics, an ellipsoid is a type of quadric that is a higher dimensional analogue of an ellipse. ... A sample of serpentinite rock, partially made up of chrysotile Serpentinite is a rock comprised of one or more serpentine minerals. ... The mineral olivine (also called chrysolite and, when gem-quality, peridot) is a magnesium iron silicate with the formula (Mg,Fe)2SiO4. ... Fig. ... Forsterite (Mg2SiO4) is the magnesium rich end-member of the olivine solid-solution series. ... Fayalite (Fe2SiO4) is the iron rich end-member of the olivine solid-solution series. ...

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Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 194th day of the year (195th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 220th day of the year (221st in leap years) in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 175th day of the year (176th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 65th day of the year (66th in leap years) in the Gregorian calendar. ... 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A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... is the 74th day of the year (75th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 75th day of the year (76th in leap years) in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 340th day of the year (341st in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 340th day of the year (341st in leap years) in the Gregorian calendar. ... is the 340th day of the year (341st in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 120th day of the year (121st in leap years) in the Gregorian calendar. ... is the 62nd day of the year (63rd in leap years) in the Gregorian calendar. ... Year 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ... For information on Wikipedia press releases, see Wikipedia:Press releases. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 69th day of the year (70th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 72nd day of the year (73rd in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 69th day of the year (70th in leap years) in the Gregorian calendar. ... is the 94th day of the year (95th in leap years) in the Gregorian calendar. ... Year 2003 (MMIII) was a common year starting on Wednesday of the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 57th day of the year in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 70th day of the year (71st in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 214th day of the year (215th in leap years) in the Gregorian calendar. ... Northern Arizona University (NAU) is a public university in Flagstaff, Arizona in the United States. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 148th day of the year (149th in leap years) in the Gregorian calendar. ... This article refers to the news department of the British Broadcasting Corporation, for the BBC News Channel see BBC News (TV channel). ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 148th day of the year (149th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 281st day of the year (282nd in leap years) in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A magnet levitating above a high-temperature superconductor demonstrates the Meissner effect. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... This article is about the European Space Agency. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 76th day of the year (77th in leap years) in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 76th day of the year (77th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 56th day of the year in the Gregorian calendar. ... “MIT” redirects here. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 57th day of the year in the Gregorian calendar. ... is the 197th day of the year (198th in leap years) in the Gregorian calendar. ... This article is about the year. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 158th day of the year (159th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 57th day of the year in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 57th day of the year in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 57th day of the year in the Gregorian calendar. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 23rd day of the year in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 201st day of the year (202nd in leap years) in the Gregorian calendar. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance with the Gregorian calendar. ... is the 18th day of the year in the Gregorian calendar. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance with the Gregorian calendar. ... is the 18th day of the year in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 214th day of the year (215th in leap years) in the Gregorian calendar. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance with the Gregorian calendar. ... is the 47th day of the year in the Gregorian calendar. ... Look up Wiley in Wiktionary, the free dictionary. ... is the 7th day of the year in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... -1... ICARUS is the official journal of the Division for Planetary Sciences of the American Astronomical Society. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 78th day of the year (79th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 86th day of the year (87th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance with the Gregorian calendar. ... is the 63rd day of the year (64th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 62nd day of the year (63rd in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 62nd day of the year (63rd in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 62nd day of the year (63rd in leap years) in the Gregorian calendar. ... is the 314th day of the year (315th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 283rd day of the year (284th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... is the 284th day of the year (285th in leap years) in the Gregorian calendar. ... Also see: 2002 (number). ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 62nd day of the year (63rd in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 166th day of the year (167th in leap years) in the Gregorian calendar. ... is the 234th day of the year (235th in leap years) in the Gregorian calendar. ... Year 2003 (MMIII) was a common year starting on Wednesday of the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 57th day of the year in the Gregorian calendar. ... This article is about the physical universe. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Science is the academic journal of the American Association for the Advancement of Science and is considered one of the worlds most prestigious scientific journals. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 57th day of the year in the Gregorian calendar. ... is the 33rd day of the year in the Gregorian calendar. ... For the band, see 1997 (band). ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 164th day of the year (165th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 60th day of the year (61st in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 124th day of the year (125th in leap years) in the Gregorian calendar. ... The Online Computer Library Center (OCLC) was founded in 1967 and originally named the Ohio College Library Center. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 140th day of the year (141st in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 140th day of the year (141st in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 60th day of the year (61st in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 60th day of the year (61st in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) was a common year starting on Monday of the Gregorian calendar in the 21st century. ... is the 60th day of the year (61st in leap years) in the Gregorian calendar. ...

External links

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Find more about Mars on Wikipedia's sister projects:
Dictionary definitions
Textbooks
Quotations
Source texts
Images and media
News stories
Learning resources
  • 3D maps of Mars in NASA World Wind
  • Google Mars – Interactive image of Mars
  • Flight Into Mariner Valley – NASA/JPL/Arizona State University 3D flythrough of Valles Marineris
  • Marsgeo.com – Mars Rover photos, videos & surface geology
  • Guide to Mars – information about Mars and how to observe it.
  • Nine Planets Mars page
  • On Mars: Exploration of the Red Planet 1958–1978 from the NASA History Office.
  • Martian Law – a CATO white paper
  • Computer Simulation of a flyby through Mariner Valley
  • Mars Unearthed – Comparisons of terrains between Earth and Mars
  • Ralph Aeschliman's Online Atlas of Mars
  • Geody Mars – World's search engine that supports NASA World Wind, Celestia, and other applications.
  • Be on Mars – Anaglyphs from the Mars Rovers (3D)
  • NASA/JPL OnMars WMS Server for Mars Data – Work as Google Earth client overlays
  • Exploring Mars: Image Center
  • Mars Astronomy Cast episode #52, includes full transcript.
  • BBC News update on Mars Express' findings of polar water ice and water-eroded features on the surface
  • BBC News Mars pictures reveal frozen sea
  • 04/02/07: ESA Prepares for a Human Mission to Mars
  • Mars' apparent relative size at opposition as seen by HST
  • Mars articles in Planetary Science Research Discoveries

Wikipedia does not have an article with this exact name. ... Image File history File links Wikibooks-logo. ... Image File history File links Wikiquote-logo. ... Image File history File links Wikisource-logo. ... Image File history File links Commons-logo. ... Image File history File links WikiNews-Logo. ... Image File history File links Wikiversity-logo-Snorky. ... A Mars Rover is an unmanned land vehicle for exploration of the planet Mars. ... Animation showing atmosphere and shading effects in v1. ... For other uses, see Celestia (disambiguation). ...

Cartographic resources

  • Mars Nomenclature
  • PDS Map-a-planet
  • Viking Photomap
  • MOLA (topographic) map


The classical albedo features of Mars are those light and dark features which can be seen on the planet Mars through an Earth-based telescope. ... Solis Lacus (85° W, 26° S) is a dark feature on Mars. ... Mars, the fourth planet from the Sun, has a very different atmosphere from that of Earth. ... For a time in the late 19th and early 20th centuries, it was believed that there were canals on Mars. ... The canals were named, by Schiaparelli and others, after real and legendary rivers of various places on Earth or the mythological underworld. ... For other uses, see Life on Mars (disambiguation). ... The North Polar Basin is a large basin in the northern region on Mars. ... This is a list of areas of chaos terrain officially named by the International Astronomical Union on the planet Mars. ... The Cydonia Region taken by the Viking 1 orbiter and released by NASA/JPL on July 25, 1976 (north is to the upper right). ... Viking mosaic of Planum Boreale and surrounds. ... Planum Australe, taken by Mars Global Surveyor. ... Mosaic of the Cerberus hemisphere of Mars Cerberus Hemisphere is a part of Mars geography and refers to the area approximately of Latitude: 20° South to 55° North and Longitude: 150° to 230°. Prominent features of the Cerberus Hemisphere include: Amazonis Planitia Cerberus Mangala Valles Utopia Planitia. ... Vastitas Borealis is the largest lowland region of Mars. ... Aram Chaos is the circular depression in the top left. ... Clouds hover over the volcano peaks of the Tharsis region in this color mosaic image. ... Ultimi Scopuli is a region near the south pole of Mars. ... Eridania Lake is a theorized ancient lake on Mars with a surface area of roughly 1. ... Olympia Undae is a large dune field on the planet Mars, located next to the north polar region of Planum Boreum and covering from 100°E to 240°E. In 2006 rich gypsum deposits were detected there by the Mars Express orbiter, suggesting that the region had been wet at... This is a list of all the named mountains on Mars. ... Olympus Mons 27km Ascraeus Mons 11km Pavonis Mons 7km Alba Patera 3km Categories: Lists of mountains by height | Mars ... Echus Montes is a large mountain on Mars at 6. ... Elysium Planitia is the second largest volcanic region on Mars, after Tharsis Montes. ... Alba Patera is a unique volcanic feature to the north of the Tharsis region of Mars, an enormous shield volcano roughly 1600 kilometers in diameter but only ~3 kilometers tall at its highest point. ... topography of Albor Tholus and its neighbourhood Albor Tholus is an extinct volcano in the Elysium Planitia area on Mars. ... Courtesy NASA/JPL-Caltech Arsia Mons is the southernmost of three volcanos (collectively known as Tharsis Montes) on the Tharsis bulge near the equator of the planet Mars. ... Courtesy NASA/JPL-Caltech Ascraeus Mons is the northernmost of three volcanos (collectively known as Tharsis Montes) on the Tharsis bulge near the equator of the planet Mars. ... Biblis Patera is an extinct Martian volcano located at 2. ... Elysium Mons is a volcano on Mars located in the Elysium Planitia, at 25°N, 213°W, in the Martian eastern hemisphere. ... Hecates Tholus is a Martian volcano, notable for results from the European Space Agencys Mars Express mission which indicate a major eruption took place 350 million years ago. ... This article is about the volcano on Mars and Solar Systems tallest mountain in Latin, For other uses, see Olympus (disambiguation). ... Pavonis Mons is the middle of three volcanos (collectively known as Tharsis Montes) on the Tharsis bulge near the equator of the planet Mars. ... Syrtis Major is a dark spot (an albedo feature) located in the boundary between the northern lowlands and southern highlands of Mars. ... Clouds hover over the volcano peaks of the Tharsis region in this color mosaic image. ... The three volcanoes that comprise Tharsis Montes: Arsia Mons is southernmost; Pavonis Mons is at center; Ascraeus Mons is at north. ... There are hundreds of thousands of craters on Mars, but only some of them have names. ... This is a list of named catenae on Mars. ... NASA image of Hellas Planitia Hellas Planitia, also known as the Hellas Impact Basin, is a roughly circular impact crater located in the southern hemisphere of the planet Mars. ... Argyre Planitia is a plain located in the Argyre impact basin in the southern highlands of Mars between -35 and -61 deg S and 27 and 62 deg W. The basin is approximately 1120 miles (1800 kilometers) wide, the second-largest impact basin on Mars after Hellas Planitia, and drops... Elevation map of Schiaparelli crater, as seen by Mars Global Surveyor. ... Gusev Crater is a meteor crater in Russia. ... Eberswalde crater, formerly known as Holden NE crater, is a partially buried impact crater in Margaritifer Terra, Mars. ... Eagle Crater is the small crater in which the Mars Exploration Rover Opportunity found itself after landing on Mars in 2004. ... False colour view of a landslide in Zunil crater The geology of Mars, also known as areology (from Greek: Ἂρης, ArÄ“s, Ares; and λόγος, logos, knowledge), refers to the study of the composition, structure, physical properties, history and the processes that shape the planet Mars. ... Evidence for carbonates on Mars has remained elusive. ... Spheules still in their originating strata Martian spherules, also known as blueberries, are the abundant spherical hematite inclusions discovered by the Mars rover Opportunity at Meridiani Planum on the planet Mars. ... Martian spiders are geological formations thus far unique to the south polar region of Mars. ... Pits in south polar ice cap, taken in consecutive southern hemesphere summers, the first of which was in 1999, the second in 2001. ... Image File history File links Mars_Hubble. ... Image File history File links Portal. ... The relative sizes of and distance between Mars, Phobos, and Deimos, to scale : Phobos (top) and Deimos (bottom). ... Phobos (IPA: or [ˈfoÊŠ.bÉ™s]) (systematic designation: ) is the larger and closer of Mars two moons (the other being Deimos). ... Deimos (IPA or ; Greek Δείμος: Dread), is the smaller and outermost of Mars’ two moons, named after Deimos from Greek Mythology. ... The discovery of the two moons of Mars, Phobos and Deimos, occurred in 1877 when American astronomer Asaph Hall, Sr. ... Phobos (IPA: or [ˈfoÊŠ.bÉ™s]) (systematic designation: ) is the larger and closer of Mars two moons (the other being Deimos). ... Deimos (IPA or ; Greek Δείμος: Dread), is the smaller and outermost of Mars’ two moons, named after Deimos from Greek Mythology. ... Stickney crater (at left), with radiating grooves Stickney at top in sunlight, imaged by Mars Global Surveyor Stickney crater is the largest crater on Phobos, which is a satellite of Mars. ... Phobos and Deimos, the two moons of Mars, are locations frequently mentioned in works of science fiction. ... A Martian meteorite is a meteorite, that has landed on Earth but is believed to have originated from Mars. ... Meteorite fragment ALH84001 ALH 84001 (Allan Hills 84001) is a meteorite found in Allan Hills, Antarctica in December 1984 by a team of US meteorite hunters from the ANSMET project. ... Thin section of Chassigny under cross-polarized light (JPL) Chassigny is a Mars meteorite that was seen to fall on October 3rd, 1815 at about 8:00 am in Chassigny, Haute-Marne, France[1][2]. Chassigny is the meteorite for which the Chassignites are named and gives rise to the... The Kaidun meteorite is a meteorite that fell on March 12, 1980 on a Soviet military base in Yemen. ... The Shergotty meteorite is the first example of the shergottite Mars meteorite family. ... The Nakhla meteorite, the first and eponymous example of a Nakhlite type meteorite of the SNC Group type of meteorites, fell to Earth on the 28th of June, 1911, at approximately 09:00 in the Nakhla region of Abu Hommos, Alexandria, Egypt. ... Computer-generated image of one of the two Mars Exploration Rovers which touched down on Mars in 2004. ... Mars Mars is the focus of much speculation and serious study about possible human colonization. ... Illustration of the Phobos spacecraft Image of Phobos taken by Phobos 2 spacecraft The Phobos program was an unmanned space mission consisting of two probes launched by the Soviet Union to study Mars and its moons Phobos and Deimos. ... The following is a list of surface features of Mars seen by the Spirit rover: // Apollo 1 Hills Columbia Hills Grissom Hill Husband Hill McCool Hill Bonneville (crater) Gusev crater Thira (crater) Adirondack (Mars) Home Plate (Mars) Pot of Gold (Mars) Larrys Lookout Sleepy Hollow (Mars) List of surface... The following is a list of surface features of Mars seen by the Opportunity rover: // Argo (crater) Eagle (crater) Emma Dean (crater) Endurance (crater) Erebus (crater) Fram (crater) Victoria (crater) Vostok (crater) Bounce Rock El Capitan Heat Shield Rock Last Chance Cape Verde (Mars) Meridiani Planum Terra Meridiani List of... HiRISE The High Resolution Imaging Science Experiment camera is a camera onboard the Mars Reconaissance Orbiter. ... Artists conception of a human mission on the surface of Mars A human mission to Mars (sometimes, manned mission to Mars) refers to humans going to the planet Mars, including orbiting Mars, landing on the surface, or walking on the surface. ... A Mars landing is when a spacecraft lands on the surface of Mars. ... A Mars Rover is an unmanned land vehicle for exploration of the planet Mars. ... Artificial objects on Mars that are currently in use are the MER-A Spirit rover and the MER-B Opportunity rover. ... Artists conception of the process of terraforming Mars Since the origin of the idea of terraforming, or changing a planets environment to produce a world that is habitable by humans, one of the primary subjects of study for potential terraforming has been the planet Mars. ... There are very few or no other articles that link to this one. ... 2003 Transit of Mercury The term transit or astronomical transit has two meanings in astronomy: A transit is the astronomical event that occurs when one celestial body appears to move across the face of another celestial body, as seen by an observer at some particular vantage point. ... Deimos transits the Sun, as seen by Mars Rover Opportunity on March 4, 2004 A transit of Deimos across the Sun as seen from Mars takes place when Deimos passes directly between the Sun and a point on the surface of Mars, obscuring a small part of the Suns... Phobos transits the Sun, as seen by Mars Rover Opportunity on March 10, 2004 A transit of Phobos across the Sun as seen from Mars takes place when Phobos passes directly between the Sun and a point on the surface of Mars, obscuring a large part of the Suns... Earth and Moon transiting the Sun in 2084, as seen from Mars Earth and Moon from Mars, as imaged by Mars Global Surveyor A transit of Earth across the Sun as seen from Mars takes place when the planet Earth passes directly between the Sun and Mars, obscuring a small... A transit of Mercury across the Sun as seen from Mars takes place when the planet Mercury passes directly between the Sun and Mars, obscuring a small part of the Suns disc for an observer on Mars. ... A transit of Venus across the Sun as seen from Mars takes place when the planet Venus passes directly between the Sun and Mars, obscuring a small part of the Suns disc for an observer on Mars. ... A Mars-crosser asteroid is an asteroid whose orbit crosses that of Mars. ... This article presents information and images about viewing astronomical phenomena from the planet Mars. ... The Darian Calendar is a system of time-keeping designed to serve the needs of any possible future human settlers on the planet Mars. ... Various schemes have been used or proposed to keep track of time and date on the planet Mars independently of Earth time and calendars. ... The Haughton-Mars Project (HMP) is an international interdisciplinary field research project being carried out near the Haughton impact crater on Canadas northern Devon Island. ... This article is about hypothetical native inhabitants of the planet Mars. ... The Mars Society is an international space advocacy non-profit organization dedicated to encouraging the exploration and settlement of Mars. ... Mars flag While not official in any legal sense, the Mars tricolor has not only been approved by the Mars Society and The Planetary Society, it has also flown in space. ... Fictional representations of Mars have been popular for over a century. ... This article is about the Solar System. ... Sol redirects here. ... This article is about the planet. ... For other uses, see Venus (disambiguation). ... This article is about Earth as a planet. ... Spectral type: G[8] Absolute magnitude: 3. ... For other uses, see Jupiter (disambiguation). ... This article is about the planet. ... For other uses, see Uranus (disambiguation). ... For other uses, see Neptune (disambiguation). ... For other uses, see Pluto (disambiguation). ... Absolute magnitude: −1. ... This article is about the astronomical term. ... Artists impression of Pluto (background) and Charon (foreground). ... A natural satellite or moon is a celestial body that orbits a planet or smaller body, which is called the primary. ... This article is about Earths moon. ... The relative sizes of and distance between Mars, Phobos, and Deimos, to scale : Phobos (top) and Deimos (bottom). ... Jupiters 4 Galilean moons, in a composite image comparing their sizes and the size of Jupiter (Great Red Spot visible). ... The Saturnian system (photographic montage) Moons of Saturn (photographic montage) Saturn has 60 confirmed natural satellites, plus three hypothetical moons. ... Uranus has twenty-seven known moons. ... Neptune (top) and Triton (bottom), 3 days after the Voyager 2 flyby. ... Hubble image of the Plutonian system Pluto has three known moons. ... Dysnomia (officially designated (136199) Eris I Dysnomia) is a moon of the dwarf planet Eris. ... A Small Solar System Body (SSSB) is a term defined in 2006 by the International Astronomical Union to describe objects in the Solar System that are neither planets nor dwarf planets: [1] This encompasses: all minor planets apart from the dwarf planets, : the classical asteroids, (except for 1 Ceres, the... Meteor redirects here. ... For other uses, see Asteroid (disambiguation). ... 243 Ida and its moon Dactyl An asteroid moon is an asteroid that orbits another asteroid. ... For other uses, see Asteroid (disambiguation). ... The centaurs are a class of icy planetoids that orbit the Sun between Jupiter and Neptune, named after the mythical race of centaurs. ... A trans-Neptunian object (TNO) is any object in the solar system that orbits the sun at a greater distance on average than Neptune. ... The Kuiper belt, derived from data from the Minor Planet Center. ... Eris, the largest known scattered disc object (center), and its moon Dysnomia (left of center). ... Comet Hale-Bopp Comet West For other uses, see Comet (disambiguation). ... Artists rendering of the Oort cloud and the Kuiper Belt. ... Astronomical objects are significant physical entities, associations or structures which current science has confirmed to exist in space. ... Below is a list of solar system objects with diameter >500km: The Sun, a spectral class G2 star Mercury Venus Earth Moon Mars Jupiter Io Europa Ganymede Callisto complete list of Jupiters natural satellites Saturn Tethys Dione Rhea Titan Iapetus complete list of Saturns natural satellites Uranus Ariel... It has been suggested that Planetary-size comparison be merged into this article or section. ... This is a list of solar system objects by mass, in decreasing order. ...


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Mars (2243 words)
The southern hemisphere of Mars is predominantly ancient cratered highlands somewhat similar to the Moon.
Mars' thin atmosphere produces a greenhouse effect but it is only enough to raise the surface temperature by 5 degrees (K); much less than what we see on Venus and Earth.
Mars is a difficult but rewarding target for an amateur telescope though only for the three or four months each martian year when it is closest to Earth.
Mars Introduction (2567 words)
Mars is the fourth planet from the Sun and is commonly referred to as the Red Planet.
The average recorded temperature on Mars is -63° C (-81° F) with a maximum temperature of 20° C (68° F) and a minimum of -140° C (-220° F).
One of the discoveries of the Mariner 9 spacecraft was that the south polar cap of Mars was made of thin layers or laminations of ice and sediment.
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