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Encyclopedia > Voyager program
The trajectories that enabled Voyager spacecraft to visit the outer planets and achieve velocity to escape our solar system

Both missions have gathered large amounts of data about the gas giants of the solar system, of which little information was known. In addition, the spacecraft trajectories have been used to place limits on the existence of a hypothetical post-Plutonian Planet X. This article does not cite any references or sources. ... Major features of the Solar System (not to scale; from left to right): Pluto, Neptune, Uranus, Saturn, Jupiter, the asteroid belt, the Sun, Mercury, Venus, Earth and its Moon, and Mars. ... Adjectives: Plutonian Atmosphere Surface pressure: 0. ... Planet X is a large hypothetical planet with an orbit beyond that of Neptune. ...

## Contents

The Voyager probes were originally conceived as part of the Mariner program, and designated Mariner 11 and Mariner 12, respectively. They were then moved into a separate program named Mariner Jupiter-Saturn, later retitled Voyager because it was more appealing and romantic. Voyager is a scaled-back version of the Grand Tour program of the late 1960s and early 1970s. The Grand Tour's plan was to send a pair of probes to fly by all the outer planets; it was scaled back because of budget cuts. However, in the end, Voyager fulfilled all the Grand Tour flyby objectives except for Pluto, which at the time was considered a planet by the IAU. 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. ... Categories: Jupiter | Saturn | NASA probes | Astronomy stubs ... Categories: Jupiter | Saturn | Uranus | Neptune | NASA probes | Astronomy stubs ... For other uses of the term Grand Tour, see Grand Tour (disambiguation) The Planetary Grand Tour was an ambitious plan to send unmanned probes to the outermost planets of the solar system. ... Logo of the IAU The International Astronomical Union (French: Union astronomique internationale) unites national astronomical societies from around the world. ...

Voyager 1 is thought to have penetrated the termination shock in late 2004

Periodic contact has been maintained with both probes to monitor conditions in the outer expanses of the solar system. The crafts' radioactive power sources are still producing electrical energy, fuelling hopes of locating the solar system's heliopause. In late 2003, Voyager 1 began sending data that seemed to indicate it had crossed the termination shock, but interpretations of this data are in dispute. It is now believed that the termination shock was crossed in December 2004, with the heliopause an unknown distance ahead. Radioactive decay is the set of various processes by which unstable atomic nuclei (nuclides) emit subatomic particles. ... The heliopause is the boundary between the heliosphere and the interstellar medium outside the solar system. ... Trajectory of Voyager 1 using Celestia The Voyager 1 spacecraft is a 733-kilogram robotic space probe of the outer solar system and beyond, launched September 5, 1977, and is currently operational. ... The locations of Voyagers 1 and 2 as of 2005 In space physics, the termination shock is the boundary marking one of the outer limits of the suns influence. ...

Due to budget shifts prompted by President George W. Bush's Vision for Space Exploration, it was rumored that the probes were to be deactivated and abandoned[1] as early as October 2005, before they would have observed the heliopause. However, the program continues to be funded into 2007. George Walker Bush (born July 6, 1946) is an American politician and the 43rd and current President of the United States. ... 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. ... The heliopause is the boundary between the heliosphere and the interstellar medium outside the solar system. ...

Location and trajectories of Pioneer and Voyager spacecraft as of April 4, 2007

As of April 4, 2007, Voyager 1 is over 15.18 terameters (15.18×1012 meters, or 15.18×109 km, 101.4 AU, or 9.4 billion miles) from the Sun, and has thus entered the heliosheath, the termination shock region between the solar system and interstellar space, a vast area where the Sun's influence gives way to the other bodies in the galaxy. As of September, 2006, Voyager 2 is at a distance of around 80.5 AU (approximately 12 terameters) from the Sun, deep in the scattered disc, and traveling outward at roughly 3.3 AUs a year. It is more than twice the distance from the Sun as Pluto. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... is the 94th day of the year (95th in leap years) in the Gregorian calendar. ... Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... A terametre (American spelling: terameter) (symbol: Tm) is a unit of length equal to 1012 metres. ... The astronomical unit (AU or au or a. ... One thousand million (1,000,000,000) is the natural number following 999,999,999 and preceding 1,000,000,001. ... The locations of Voyagers 1 and 2 as of 2005 The heliosheath is the zone between the termination shock and the heliopause at the outer border of the solar system. ... The locations of Voyagers 1 and 2 as of 2005 In space physics, the termination shock is the boundary marking one of the outer limits of the suns influence. ... The interstellar medium (or ISM) is the name astronomers give to the tenuous gas and dust that pervade interstellar space. ... This article does not cite any references or sources. ... Year 2006 (MMVI) was a common year starting on Sunday (link displays full 2006 calendar) of the Gregorian calendar. ... The astronomical unit (AU or au or a. ... tera- (symbol: T) is a prefix in the SI system of units denoting 1012, or 1 000 000 000 000. ... The Sun (Latin: ) is the star at the center of the Solar System. ... The scattered disc (or scattered disk) is a distant region of our solar system, thinly populated by icy planetoids known as scattered disk objects (SDOs), a subset of the broader family of trans-Neptunian objects (TNOs). ... Adjectives: Plutonian Atmosphere Surface pressure: 0. ...

## Spacecraft design

Artist's concept of Voyager in flight

The Imaging Science Subsystem, made up of a wide angle and a narrow angle camera, is a modified version of the slow scan vidicon camera designs that were used in the earlier Mariner flights. The Imaging Science Subsystem consists of two television-type cameras, each with 8 filters in a commandable Filter Wheel mounted in front of the vidicons. One has a low resolution 200 mm wide-angle lens with an aperture of f/3 (Wide Angle Camera), while the other uses a higher resolution 1500 mm narrow-angle f/8.5 lens (Narrow Angle Camera). In older video cameras, prior to the 1990s, a video camera tube or pickup tube was used instead of a charge-coupled device (CCD). ...

Unlike the other onboard instruments, operation of the cameras is not autonomous, but is controlled by an imaging parameter table residing in one of the spacecraft computers, the Flight Data Subsystem (FDS).

The computer command subsystem (CCS) provides sequencing and control functions. The CCS contains fixed routines such as command decoding and fault detection and corrective routines, antenna pointing information, and spacecraft sequencing information. The Voyager spacecraft have three RCA 1802 CPUs running at 6.4 MHz. These CPUs sent to space were operating at full military specification temperatures (-55 to +125 °C). The RCA (CDP)1802 (aka RCA COSMAC*, COSMAC 1802) is an 8-bit CMOS microprocessor (ÂµP) introduced by RCA in early 1976, and presently being manufactured by Intersil Corporation. ... CPU can stand for: in computing: Central processing unit in journalism: Commonwealth Press Union in law enforcement: Crime prevention unit in software: Critical patch update, a type of software patch distributed by Oracle Corporation in Macleans College is often known as Ash Lim. ...

The Attitude and Articulation Control Subsystem (AACS) controls the spacecraft orientation, maintains the pointing of the high-gain antenna towards Earth, controls attitude maneuvers, and positions the scan platform. The high-gain antenna (HGA) is an antenna with a focused, narrow radiowave beam width. ...

Uplink communications is via S band (16-bit/s command rate) while an X band transmitter provides downlink telemetry at 160 bit/s normally and 1.4 kbit/s for playback of high-rate plasma wave data. All data is transmitted from and received at the spacecraft via the 3.7-meter high-gain antenna (HGA). Look up uplink in Wiktionary, the free dictionary. ... The S band ranges from 2 to 4 GHz. ... In telecommunications and computing, bit rate (sometimes written bitrate) is the frequency at which bits are passing a given (physical or metaphorical) point. It is quantified using the bit per second (bit/s) unit. ... The X band (3-cm radar spot-band) of the microwave band of the electromagnetic spectrum roughly ranges from 5. ...

### Power

Radioisotope thermoelectric generators for the Voyager program.

Electrical power is supplied by three radioisotope thermoelectric generators (RTGs). They are powered by plutonium-238 (distinct from the Pu-239 isotope used in nuclear weapons) and provided approximately 470 W at 30 volts DC when the spacecraft was launched. Plutonium-238 decays with a half-life of 87.74 years, [3] so RTGs using Pu-238 will lose a factor of $1 - sqrt[87.74]{0.5}$ of their power output per year. In 2006, 29 years after launch, such an RTG would produce only 470 W × 2-(29/87.74) ~= 373 W — or about 79.5% — of its initial power. However, the bi-metallic thermocouples that convert heat into electricity also degrade, so the actual power will be even lower. As of August 11th, 2006, the power generated by Voyager 1 and Voyager 2 had dropped to 290 W and 291 W respectively, about 60% of the power at launch. This is better than the pre-launch predictions based on a conservative thermocouple degradation model. As the electrical power decreases, spacecraft loads must be turned off, eliminating some spacecraft capabilities. Image File history File links Download high-resolution version (536x676, 193 KB) Two Multi Hundred Watt (MHW) Radioisotope thermoelectric generators (RTG) for the Voyager program. ... Image File history File links Download high-resolution version (536x676, 193 KB) Two Multi Hundred Watt (MHW) Radioisotope thermoelectric generators (RTG) for the Voyager program. ... Transmission lines in Lund, Sweden Electric power, often known as power or electricity, involves the production and delivery of electrical energy in sufficient quantities to operate domestic appliances, office equipment, industrial machinery and provide sufficient energy for both domestic and commercial lighting, heating, cooking and industrial processes. ... // A radioisotope thermoelectric generator (RTG) is a simple electrical generator which obtains its power from radioactive decay. ... General Name, Symbol, Number plutonium, Pu, 94 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery white Standard atomic weight (244) gÂ·molâˆ’1 Electron configuration [Rn] 5f6 7s2 Electrons per shell 2, 8, 18, 32, 24, 8, 2 Physical properties Phase solid Density (near r. ... The watt (symbol: W) is the SI derived unit of power, equal to one joule per second. ... Josephson junction array chip developed by NIST as a standard volt. ... Direct current (DC or continuous current) is the continuous flow of electricity through a conductor such as a wire from high to low potential. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... In electronics, thermocouples are a widely used type of temperature sensor and can also be used as a means to convert thermal potential difference into electric potential difference. ... For other uses, see Heat (disambiguation) In physics, heat, symbolized by Q, is energy transferred from one body or system to another as a result of a difference in temperature. ... Lightning strikes during a night-time thunderstorm. ...

### Powering down

As of the present date, the entire Voyager 2 and Voyager 1 scan platform, including all of the platform instruments, has been powered down. The ultraviolet spectrometer (UVS)[4] on Voyager 1 was active until 2003, when it too was deactivated. Gyro operations will end in 2010 for Voyager 2 and 2011 for Voyager 1. Gyro operations are used to rotate the probe 360 degrees six times a year to measure the magnetic field of the spacecraft, which is then subtracted from the magnetometer science data. Magnetic field lines shown by iron filings In physics, a magnetic field is a solenoidal vector field in the space surrounding moving electric charges and magnetic dipoles, such as those in electric currents and magnets. ... A magnetometer is a scientific instrument used to measure the strength and/or direction of the magnetic field in the vicinity of the instrument. ...

The two Voyager spacecraft continue to operate, with some loss in subsystem redundancy, but retain the capability of returning scientific data from a full complement of VIM science instruments. Both spacecraft also have adequate electrical power and attitude control propellant to continue operating until around 2020, when the available electrical power will no longer support science instrument operation. At this time, science data return and spacecraft operations will cease.

## Voyager Golden Record

Main article: Voyager Golden Record

Voyager 1 and 2 both carry with them a golden record that contains pictures and sounds of Earth, along with symbolic directions for playing the record and data detailing the location of Earth. The record is intended as a combination time capsule and interstellar message to any civilization, alien or far-future human, that recovers either of the Voyager craft. The contents of this record were selected by a committee chaired by Carl Sagan. The Voyager Golden Record. ... Insert non-formatted text here Carl Edward Sagan (November 9, 1934 â€“ December 20, 1996) was an American astronomer and astrobiologist and a highly successful popularizer of astronomy, astrophysics, and other natural sciences. ...

## Fiction and popular culture

The Voyager launches occurred just before the dawn of the media-savvy 1980s, and the program's discoveries during the primary phase of its mission, including striking never-before-seen close up color photos of the major planets, were regularly documented by both print and electronic media outlets. As a result, the Voyager program, especially at the high points of its mission, has seen significant public limelight. As a result, there are a number of references to the Voyager program or to the particular probes themselves within popular culture.

The section Voyager 2 in fiction and popular culture in the Voyager 2 article contains specific references to Voyager 2 in pop culture.
• Star Trek: The Motion Picture has as its premise an alien intelligence, V'ger which turns out to be the fictional Voyager 6. It is able to show the character Spock its history through holographic recordings, analogous to the Voyager Golden Disk, and is on a journey back to earth to bond with its creator.
• In the animated television series Beast Wars: Transformers, the Predacon leader Megatron travels back in time and uses data encoded on Voyager 1's golden disk as a guide to altering Earth's history. "Code of Hero", "The Agenda: Part 2"
• Stephen Baxter's novel Titan (1997) describes what will happen to the Voyager probes billions of years in the future as the metal from which they are constructed gradually disintegrates.
• In L. Ron Hubbard's novel Battlefield Earth, aliens who stumble on Voyager and its golden contents proceed to find and conquer Earth.
• John Carpenter's 1984 movie Starman opens with the Voyager 1 probe being intercepted by an alien spacecraft, whose occupants play the golden record. Accepting its invitation of friendship, the aliens send an emissary to visit Earth. Upon arrival, the emissary is shot down by US Fighter planes. The alien then assumes the form of a widow's deceased husband (Jeff Bridges) to make the hazardous journey to rendezvous with his mother-ship at Meteor Crater, Arizona. During the journey, the alien frequently sings or quotes excerpts from the soundtrack of Voyager's golden record.
• In the Futurama episode "Parasites Lost" in Season 3, Leela is seen cleaning the wreckage of one of the Voyager probes from the windshield of the Planet Express spaceship with a squeegee.
• In a Warren Fu's Kubrick-esque music video for The StrokesYou Only Live Once, a spacecraft leaves Earth for Sirius with a golden record containing the band's song and graphics and images of: greetings in different human languages; human evolution; human biology; the structure of DNA; and human reproduction. At the end of the film, the text "1977 A.D." precedes the end title.

Trajectory Voyager 2 is an unmanned interplanetary spacecraft, launched on August 20, 1977. ... Star Trek: The Motion Picture (Paramount Pictures, 1979; see also 1979 in film) is the first feature film based on the popular Star Trek science fiction television series and is released on Friday, December 7. ... Vger (Vejur in the novelization by Gene Roddenberry) is a fictional character in the Star Trek universe. ... For other uses, see Spock (disambiguation). ... The starship Voyager (NCC-74656), an Intrepid-class starship. ... Life Line is an episode from the sixth season of Star Trek: Voyager. ... In the fictional Star Trek universe, Dr. Lewis Zimmerman is the creator of the Emergency Medical Hologram, or EMH. Dr. Zimmerman is the Director of Holographic imaging and Programming on Jupiter Station, and is regarded as the father of modern holography. ... Pioneer 10 was the first spacecraft to travel through the asteroid belt, and was the first spacecraft to make direct observations of Jupiter. ... Position of Pioneer 10 and 11 Pioneer 11 was the second mission to investigate Jupiter and the outer solar system and the first to explore the planet Saturn and its main rings. ... Trajectory of Voyager 1 using Celestia The Voyager 1 spacecraft is a 733-kilogram robotic space probe of the outer solar system and beyond, launched September 5, 1977, and is currently operational. ... Trajectory Voyager 2 is an unmanned interplanetary spacecraft, launched on August 20, 1977. ... Pathfinder is a term occasionally used to describe the first ship in a given class of starship, and is used to describe the USS Galaxy in the Star Trek: The Next Generation Technical Manual. ... 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. ... The Predacons are one of the many factions in the fictional Transformers Universes. ... This article or section contains a plot summary that is overly long or excessively detailed. ... The Earth, photographed from Apollo 17 in 1972. ... Stephen Baxter (born in Liverpool, 13 November 1957) is a British hard science fiction author. ... Titan is a 1997 science fiction novel by Stephen Baxter. ... Battlefield Earth is the title of both a science fiction novel written by Scientology founder L. Ron Hubbard, and a film adaptation of the novel produced by and starring John Travolta. ... X-Files intro from first 8 seasons The X-Files was a popular 1990s American science fiction television series created by Chris Carter. ... Special Agent Fox William Mulder (born October 13, 1961), nicknamed Spooky Mulder, is a fictional character played by David Duchovny on the 1993-2002 television series, The X-Files. ... David William Duchovny (born August 7, 1960) is a Golden Globe Award-winning American television and film actor perhaps best known for his role as Fox Mulder on The X-Files. ... The Arecibo Observatory is located approximately 9 miles south-southwest from Arecibo, Puerto Rico (near the extreme southwestern corner of Arecibo pueblo). ... The six Brandenburg concertos (BWV 1046-1051) by Johann Sebastian Bach are a collection of instrumental works presented by Bach to the Margrave of Brandenburg in 1721, but probably composed earlier. ... Bach in a 1748 portrait by Haussmann Places in which Bach resided throughout his life Johann Sebastian Bach (pronounced ) (21 March 1685 O.S. â€“ 28 July 1750 N.S.) was a prolific German composer and organist whose sacred and secular works for choir, orchestra and solo instruments drew together the... John Howard Carpenter (born January 16, 1948) is an American film director, screenwriter, producer, film score composer and occasional actor. ... Starman (1984; see also 1984 in film) is a science fiction film directed by John Carpenter which tells the story of an alien from another planet (Jeff Bridges) who has come to Earth in response to the invitation left of the gold phonograph record on the Voyager space probes. ... Jeffrey Leon Bridges (born December 4, 1949) is an Academy Award-nominated American actor. ... Futurama is an Emmy Award-winning animated American sitcom created by Matt Groening, also the creator of The Simpsons, and developed by Groening and David X. Cohen for the Fox network. ... Squeegee, sponge, and chalk on a desk. ... â€œKubrickâ€ redirects here. ... The Strokes are an American rock band formed in 1998 that rose to fame in the early 2000s as a leading group in the garage rock revival. ... You Only Live Once is the opening track and third single from First Impressions of Earth, the third album from American rock band The Strokes. ... Sirius (Î± CMa / Î± Canis Majoris / Alpha Canis Majoris) (IPA: ) is the brightest star in the night-time sky with a visual apparent magnitude of âˆ’1. ...

## Notes and references

1. ^ "Voyager probes in funding crisis", BBC, March 10, 2005.
2. ^ -Nasa Website Voyager
3. ^ http://lanl.gov/source/orgs/nmt/nmtdo/AQarchive/97summer/Pu_238.html
4. ^ Ultraviolet Spectrometer. Voyager: The Interstellar Mission. NASA JPL. Retrieved on 2006-06-11.

Year 2006 (MMVI) was a common year starting on Sunday (link displays full 2006 calendar) of the Gregorian calendar. ... is the 162nd day of the year (163rd in leap years) in the Gregorian calendar. ...

Dictionary definitions from Wiktionary
Textbooks from Wikibooks
Quotations from Wikiquote
Source texts from Wikisource
Images and media from Commons
News stories from Wikinews
Learning resources from Wikiversity

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. ... Timeline of planetary exploration by date of launch. ... Trajectory of Voyager 1 using Celestia The Voyager 1 spacecraft is a 733-kilogram robotic space probe of the outer solar system and beyond, launched September 5, 1977, and is currently operational. ... Trajectory Voyager 2 is an unmanned interplanetary spacecraft, launched on August 20, 1977. ... The Voyager Golden Record. ... Pioneer 10 was the first spacecraft to travel through the asteroid belt, and was the first spacecraft to make direct observations of Jupiter. ... Position of Pioneer 10 and 11 Pioneer 11 was the second mission to investigate Jupiter and the outer solar system and the first to explore the planet Saturn and its main rings. ... The family portrait taken by Voyager 1 The Family Portrait, or Portrait of the Planets is an image of the Solar System created by Voyager 1 on February 14, 1990; the last taken by the spacecraft before it began its mission into interstellar space. ... The National Aeronautics and Space Administration (NASA) is an agency of the United States government, responsible for the nations public space program. ... The Explorer program was the United Statess first successful attempt to launch an artificial satellite . ... NASAs New Millennium program is focused on engineering validation of new technologies for space applications. ... NASAs Discovery Program is a series of lower-cost, highly focused scientific space missions. ... NASAs New Frontiers Program is a series of medium-cost (not to exceed 700 million), highly focused scientific space missions. ... Artists Concept of Rover on Mars (credit: Maas Digital LLC) NASAs Mars Exploration Rover (MER) Mission is an ongoing robotic Mars exploration mission, commenced in 2003, that sent two rovers â€” Spirit and Opportunity â€” to explore the Martian surface and geology. ... Nuclear reactors may be used to power ion engines such as this one used on Deep Space 1 Project Prometheus was established in 2003 by NASA to develop nuclear-powered systems for long-duration space missions. ... Project Constellation is NASAs current plan for space exploration. ... The Mars Scout Program is a new NASA program of small, low-cost missions to Mars, selected from innovative proposals by the scientific community. ... The Mars Scout Program is a new NASA program of small, low-cost missions to Mars, selected from innovative proposals by the scientific community. ... The US Pioneer program of unmanned space missions was designed for planetary exploration. ... 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. ... Lunar orbiter spacecraft (NASA) The Lunar Orbiter program was a series of five unmanned Lunar orbiter missions launched by the United States in 1966 through 1967 with the purpose of mapping the lunar surface before the Apollo landings. ... The Ranger program was a series of unmanned space missions by the United States in the 1960s whose objective was to obtain the first close-up images of the surface of the Moon. ... Photograph of Surveyor(3) lunar landing spacecraft taken by Apollo 12 astronauts (descriptions added). ... For other uses, see Apollo (disambiguation). ... Viking mission profile. ... NASAs Planetary Observer series was still birthed, resulting in only one, failed, mission. ... Mariner Mark II was NASAs planned family of unmanned spacecraft for the exploration of the outer solar system that were to be developed and operated by JPL between 1990 thru the year 2010. ... The Mars Surveyor 98 program comprised two spacecraft launched separately, the Mars Climate Orbiter (formerly the Mars Surveyor 98 Orbiter) and the Mars Polar Lander (formerly the Mars Surveyor 98 Lander); on board the Mars Polar Lander spacecraft were two surface-penetrator probes (Deep Space 2). ... For other uses of the term Grand Tour, see Grand Tour (disambiguation) The Planetary Grand Tour was an ambitious plan to send unmanned probes to the outermost planets of the solar system. ... The Voyager program was a planned series of unmanned NASA probes to Mars. ...

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 Voyager 2 at AllExperts (2725 words) Voyager 2 is arguably the most prolific space probe ever launched from Earth, visiting 4 planets and their many moons with powerful cameras and a multitude of scientific instruments, at a fraction of the money later spent on specialized probes such as the Galileo spacecraft and the Cassini-Huygens probe. Voyager 2 found that at the highest levels (7 kilopascal pressure) Saturn's temperature was 70 kelvin (â'203 Â°C), while at the deepest levels measured (120 kilopascal) the temperature increased to 143 kelvin (â'130 Â°C). Voyager 2 found that one of the most striking influences of this sideways position is its effect on the tail of the magnetic field, which is itself tilted 60 degrees from the planet's axis of rotation.
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