A geostationary transfer orbit (GTO) is a Hohmann transfer orbit around the Earth between a low Earth orbit (LEO) and a geostationary orbit (GEO). It is an ellipse where the perigee is a point on a LEO and the apogee has the same distance from the Earth as the GEO. In astronautics and aerospace engineering, the Hohmann transfer orbit is an orbital maneuver that, under standard assumption, moves a spacecraft from one circular orbit to another using two engine impulses. ...
This article is about Earth as a planet. ...
A low Earth orbit (LEO) is an orbit in which objects such as satellites are below intermediate circular orbit (ICO) and far below geostationary orbit, but typically around 350  1400 km above the Earths surface. ...
Geostationary orbit A geostationary orbit (GEO) is a geosynchronous orbit directly above the Earths equator (0Â° latitude), with orbital eccentricity of zero. ...
For other uses, see Ellipse (disambiguation). ...
Perigee is the point at which an object in orbit around the Earth makes its closest approach to the Earth. ...
More generally, a geostationary transfer orbit is an intermediate orbit between a LEO and a geosynchronous orbit. It has been suggested that this article or section be merged with geostationary orbit. ...
After a typical launch the inclination of the LEO (the angle between the plane of the orbit and the plane of the equator) is determined by the latitude of the launch site and the direction of launch. The GTO inherits the same inclination. The inclination must be reduced to zero to obtain a geostationary orbit. This is done at the GEO distance because that requires less energy than at LEO. This is because the required deltav (Δv) for a certain inclination change Δi is directly proportional to orbit velocity v which is lowest in its apogee. The required deltav for an inclination change in either the ascending or descending node of the orbit is calculated as follows: For the science fiction novella by William Shunn, see Inclination (novella). ...
World map showing the equator in red In tourist areas, the equator is often marked on the sides of roads The equator marked as it crosses IlhÃ©u das Rolas, in SÃ£o TomÃ© and PrÃncipe. ...
This article is about the geographical term. ...
General In general physics deltav is simply the change in velocity. ...
This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ...
General In general physics deltav is simply the change in velocity. ...
The ascending node is one of the orbital nodes, a point in the orbit of an object where it crosses the plane of the ecliptic from the south celestial hemisphere to the north celestial hemisphere in the direction of motion. ...
The descending node is the point in the orbit of an object where it crosses the plane of the ecliptic from the north celestial hemisphere to the south celestial hemisphere in the direction of motion. ...
Assuming a typical Ariane 5 GTO with a semimajor axis of 24,582 km, the perigee velocity of a GTO is 9.88 km/s while the apogee velocity is at 1.64 km/s. In geometry, the semimajor axis (also semimajor axis) a applies to ellipses and hyperbolas. ...
Perigee is the point at which an object in orbit around the Earth makes its closest approach to the Earth. ...
This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ...
A launch vehicle can move from LEO to GTO by firing a rocket at a tangent to the LEO to increase its velocity. Typically the upper stage of the vehicle has this function. Once in the GTO, it is usually the satellite itself that performs the conversion to geostationary orbit by firing a rocket at a tangent to the GTO at the apogee. Therefore the capacity of a rocket which can launch various satellites is often quoted in terms of separated spacecraft mass to GTO rather than ditto to GEO. Alternatively the rocket may have the option to perform the boost for insertion into GEO itself. This saves the satellite's fuel, but considerably reduces the separated spacecraft mass capacity. This article is about vehicles powered by rocket engines. ...
For other uses, see tangent (disambiguation). ...
Geostationary orbit A geostationary orbit (GEO) is a geosynchronous orbit directly above the Earths equator (0Â° latitude), with orbital eccentricity of zero. ...
For example, the capacity (separated spacecraft mass) of the Delta IV Heavy: It has been suggested that some sections of this article be split into a new article entitled Delta IV launches. ...
 GTO 12 757 kg (185 km x 35,786 km at 27.0 deg inclination), theoretically more than any other currently available launch vehicle (has not flown with such a payload yet)
 GEO 6 276 kg
Usually, insertion into geostationary orbit is performed at the ascending node. This is because most launch sites from which launches into a GTO are performed are located on the northern hemisphere. Geostationary orbit A geostationary orbit (GEO) is a geosynchronous orbit directly above the Earths equator (0Â° latitude), with orbital eccentricity of zero. ...
In most cases, the spent upper stages of launch vehicles are left behind in the GTO (some are occasionally left in GEO, like the Proton Block DM). If the perigee of the GTO is chosen to be low enough to make atmospheric drag quickly decrease apogee altitude, the upper stage will be no collision threat to the satellites in the geostationary ring. Eventually, it will reenter the atmosphere of the Earth. Most upper stages that are used to bring payloads to a GTO are designed to meet this requirement. Perigee is the point at which an object in orbit around the Earth makes its closest approach to the Earth. ...
This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ...
The geostationary ring is a volume segment around the geostationary orbit defined by variations in altitude and declination that can occur for uncontrolled objects left in the geostationary orbit. ...
Heavy Lift Launch Vehicles are the only rockets capable of moving heavier satellites into geostationary or geosynchronous orbits. The capability of achieving geostationary transfer orbit is critical to the placement of modern satellites, as well as to the success of space programs going to the Moon, Mars, and the outer parts of the solar system. The reason for this is that the GTO is an orbit cycling between a perigee tangent to LEO and an apogee tangent to a geostationary orbit. At the point where the orbit is tangent to the geostationary orbit, the payload can conduct a controlled burn and insert itself into the geostationary orbit, where it will hold its position 22,240 miles (35,792 kilometres) over a specific spot on the equator. By contrast, geosynchronous orbits have the same period of orbit as the Earth has of rotation (24 hours), but the orbits themselves may be elliptical, and can also be outside of an equatorial orbit. The proposed ShuttleC HLLV A Heavy Lift Launch Vehicle, or HLLV, is distinguished from Medium Lift Launch Vehicles (MLLV) by the mass that they can lift into Low Earth Orbit (LEO). ...
Two bodies with a slight difference in mass orbiting around a common barycenter. ...
This article is about Earths moon. ...
Adjectives: Martian Atmosphere Surface pressure: 0. ...
Two bodies with a slight difference in mass orbiting around a common barycenter. ...
Perigee is the point at which an object in orbit around the Earth makes its closest approach to the Earth. ...
This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ...
Geostationary orbit A geostationary orbit (GEO) is a geosynchronous orbit directly above the Earths equator (0Â° latitude), with orbital eccentricity of zero. ...
It has been suggested that this article or section be merged with geostationary orbit. ...
Equatorial orbit is an orbit with inclination to the plane of reference (i. ...
See also
Orbits  Orbital parameters   Classical orbital elements Inclination Longitude of the ascending node Eccentricity Astrodynamics is the study of the motion of rockets, missiles, and space vehicles, as determined from Sir Isaac Newtons laws of motion and his law of universal gravitation. ...
The following is a list of types of orbits: // Box orbit Circular orbit Ecliptic orbit Elliptic orbit Highly Elliptical Orbit Graveyard orbit Hohmann transfer orbit Hyperbolic trajectory Inclined orbit Osculating orbit Parabolic trajectory Capture orbit Escape orbit Semisynchronous orbit Subsynchronous orbit Synchronous orbit Geocentric orbit Geosynchronous orbit Geostationary orbit...
Two bodies with a slight difference in mass orbiting around a common barycenter. ...
The elements of an orbit are the parameters needed to specify that orbit uniquely, given a model of two ideal masses obeying the Newtonian laws of motion and the inversesquare law of gravitational attraction. ...
For the science fiction novella by William Shunn, see Inclination (novella). ...
The Longitude of the ascending node (â˜Š, also noted Î©) is one of the orbital elements used to specify the orbit of an object in space. ...
(This page refers to eccitricity in astrodynamics. ...
 Argument of periapsis Semimajor axis Mean anomaly at epoch The argument of periapsis (Ï‰) 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...
The semimajor axis of an ellipse In geometry, the term semimajor axis (also semimajor axis) is used to describe the dimensions of ellipses and hyperbolae. ...
In the study of orbital dynamics the mean anomaly is a measure of time, specific to the orbiting body p, which is a multiple of 2π radians at and only at periapsis. ...
In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ...
 Other parameters True anomaly Semiminor axis Linear eccentricity Eccentric anomaly In astronomy, the true anomaly (, also written ) is the angle between the direction zs of periapsis and the current position p of an object on its orbit, measured at the focus s of the ellipse (the point around which the object orbits). ...
In geometry, the semiminor axis (also semiminor axis) applies to ellipses and hyperbolas. ...
(This page refers to eccentricity in mathematics. ...
The eccentric anomaly is the angle between the direction of periapsis and the current position of an object on its orbit, projected onto the ellipses circumscribing circle perpendicularly to the major axis, measured at the centre of the ellipse. ...
 Mean longitude True longitude Orbital period In astrodynamics or celestial dynamics mean longitude of an orbiting body is . ...
In astrodynamics true longitude is a . ...
The orbital period is the time it takes a planet (or another object) to make one full orbit. ...
   Types   Maneuvers  Bielliptic transfer · Geostationary transfer · Gravity assist · Hohmann transfer · Inclination change · Phasing · Rendezvous  Related topics  Apsis · Celestial coordinate system · Deltav budget · Epoch · Ephemeris · Equatorial coordinate system · Gravity turn · Ground track · Interplanetary Transport Network · Kepler's laws of planetary motion · Lagrangian point · nbody problem · Oberth effect · Orbit equation · Orbital state vectors · Perturbation · Retrograde and direct motion · Specific orbital energy · Specific relative angular momentum  List of orbits  In stellar dynamics a box orbit refers to a particular type of orbit which can be seen in triaxial systems, that is, systems which do not possess a symmetry around any of its axes. ...
In astrodynamics or celestial mechanics a circular orbit is an elliptic orbit with the eccentricity equal to 0. ...
A noninclined orbit is an orbit which is contained in the plane of reference. ...
Two bodies with similar mass orbiting around a common barycenter with elliptic orbits. ...
Highly Elliptical Orbit (HEO) is an elliptic orbit characterized by a relatively lowaltitude perigee and an extremely highaltitude apogee. ...
A graveyard orbit is an orbit where spacecraft are intentionally placed at the end of their operational life. ...
In astrodynamics or celestial mechanics a hyperbolic trajectory is an orbit with the eccentricity greater than 1. ...
A geostationary orbit occurs when an object (satellite) is placed 37,000 km (22,300 miles) above the Earths equator with the characteristic that, from a fixed observation point on the Earths surface, it appears motionless. ...
In Astronomy, and in particular in Astrodynamics, the osculating orbit of an object in space is the gravitational Keplerian orbit about a central body which best approximates the (more complex) motion of the object at a given instant in time. ...
In astrodynamics or celestial mechanics a parabolic trajectory is an orbit with the eccentricity equal to 1. ...
A capture orbit is the highenergy parabolic orbit that allows the capture other than crashing directly to the central bodys surface (or atmospheric re_entry). ...
An escape orbit (also known as C3 = 0 orbit) is the highenergy parabolic orbit around the central body. ...
SemiSynchronous Orbit (SSO): An orbit with approximately a 12hour period. ...
Unsurprisingly similar to synchronous orbit, this orbit is at a slightly different distance from the Earth, resulting in the satellite drifting slowly eastward. ...
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. ...
A parking orbit is a temporary orbit used during the launch of a satellite or other space probe. ...
Geocentric orbit refers to the orbit of any object orbiting the Earth, such as the Moon or artificial satellites. ...
It has been suggested that this article or section be merged with geostationary orbit. ...
Geostationary orbit A geostationary orbit (GEO) is a geosynchronous orbit directly above the Earths equator (0Â° latitude), with orbital eccentricity of zero. ...
By analogy with the geosynchronous orbit, a heliosynchronous orbit is a heliocentric orbit of radius 24. ...
A low Earth orbit (LEO) is an orbit in which objects such as satellites are below intermediate circular orbit (ICO) and far below geostationary orbit, but typically around 350  1400 km above the Earths surface. ...
Intermediate circular orbit (ICO), also called medium earth orbit (MEO), is used by satellites between the altitudes of low earth orbit (up to 1400 km) and geostationary orbit (ca. ...
Molniya orbit is a class of a highly elliptic orbit with inclination of +/63. ...
A near equatorial orbit is an orbit that lies close to the equatorial plane of the object orbited. ...
The orbit of the Moon around the Earth is completed in approximately 27. ...
A polar orbit is an orbit in which a satellite passes above or nearly above both poles of the planet orbiting on each revolution. ...
Tundra orbit is a class of a highly elliptic orbit with inclination of 63. ...
Areosynchronous orbits are class of synchronous orbits for artificial satellites around the planet Mars. ...
An areostationary orbit (abbreviated ASO) is a circular areoÂsynchronous orbit in the Martian equatorial plane 11,000 km above the surface, any point on which revolves about Mars in the same direction and with the same period as the Martian surface. ...
A halo orbit is an orbit around a Lagrange point between two larger bodies. ...
In orbital mechanics, a Lissajous orbit is a quasiperiodic orbital trajectory an object can follow around a colinear libration point of a twobody system without requiring any propulsion. ...
In astronomy, lunar orbit refers just to the orbit of the Moon around the Earth. ...
A heliocentric orbit is an orbit around the sun. ...
By analogy with the geosynchronous orbit, a heliosynchronous orbit is a heliocentric orbit of radius 24. ...
An orbital maneuver is a change from one orbit to another, accomplished by applying thrust. ...
In astronautics and aerospace engineering, the Bielliptic transfer is an orbital maneuver that moves a spacecraft from one orbit to another and may, in certain situations require less deltav than a Hohmann transfer. ...
In orbital mechanics and aerospace engineering, a gravitational slingshot or gravity assist is the use of the gravity of a planet or other celestial body to alter the path and speed of a spacecraft. ...
In astronautics and aerospace engineering, the Hohmann transfer orbit is an orbital maneuver that, under standard assumption, moves a spacecraft from one circular orbit to another using two engine impulses. ...
Orbital inclination change is a orbital maneuver aimed at changing inclination of orbiting bodys orbit. ...
In astrodynamics orbital phasing is the adjustment of the timeposition of spacecraft along its orbit, usually described as adjusting the orbiting spacecrafts true anomaly. ...
A space rendezvous between two spacecraft, often between a spacecraft and a space station, is an orbital maneuver where the two arrive at the same orbit, make the orbital velocities the same, and bring them together (an approach maneuver, taxiing maneuver); it may or may not include docking. ...
A diagram of Keplerian orbital elements. ...
In astronomy, a celestial coordinate system is a coordinate system for mapping positions in the sky. ...
Deltav budget (or velocity change budget) is a term used in astrodynamics and aerospace industry for velocity change (or deltav) requirements for the various propulsive tasks and orbital maneuvers over phases of the space mission. ...
In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ...
An ephemeris (plural: ephemerides) (from the Greek word ephemeros = daily) is a device giving the positions of astronomical objects in the sky. ...
The equatorial coordinate system is probably the most widely used celestial coordinate system, whose equatorial coordinates are: declination () right ascension () also RA, or hour angle () also HA It is the most closely related to the geographic coordinate system, because they use the same fundamental plane, and the same poles. ...
ï»¿A gravity turn is a maneuver used in launching spacecraft into, and descending from, orbits around a celestial body such as a planet or a moon. ...
Ground track of the International Space Station for approximately two periods. ...
Artists concept of the Interplanetary Transport Network. ...
Johannes Keplers primary contributions to astronomy/astrophysics were his three laws of planetary motion. ...
A contour plot of the effective potential (the Hills Surfaces) of a twobody system (the Sun and Earth here), showing the five Lagrange points. ...
This article is about the problem in classical mechanics. ...
The Oberth effect is a feature of astronautics where using a rocket engine close to a gravitational body gives a higher final speed than the same burn executed further from the body. ...
In astrodynamics an orbit equation defines the path of orbiting body around central body relative to , without specifying position as a function of time. ...
In astrodynamics or celestial dynamics orbital state vectors (sometimes State Vectors) are vectors of position () and velocity () that together with their time (epoch) () uniquely determine the state of an orbiting body. ...
Perturbation is a term used in astronomy to describe alterations to an objects orbit caused by gravitational interactions with other bodies. ...
Direct motion is the motion of a planetary body in a direction similar to that of other bodies within its system, and is sometimes called prograde motion. ...
In astrodynamics the specific orbital energy (or visviva energy) of an orbiting body traveling through space under standard assumptions is the sum of its potential energy () and kinetic energy () per unit mass. ...
In astrodynamics specific relative angular momentum () of orbiting body () relative to central body () is the relative angular momentum of per unit mass. ...
The following is a list of types of orbits: // Box orbit Circular orbit Ecliptic orbit Elliptic orbit Highly Elliptical Orbit Graveyard orbit Hohmann transfer orbit Hyperbolic trajectory Inclined orbit Osculating orbit Parabolic trajectory Capture orbit Escape orbit Semisynchronous orbit Subsynchronous orbit Synchronous orbit Geocentric orbit Geosynchronous orbit Geostationary orbit...
