Exploration of Mars

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Not to be confused with Colonization of Mars.
Orbits of moons and spacecraft orbiting Mars.[1]
The Curiosity rover checks its wheels in Gale crater
Active missions at Mars
Year
2015
7
2014
7
2013
5
2012
5
2011
4
2010
5
2009
5
2008
6
2007
5
2006
6
2005
5
2004
5
2003
3
2002
2

The exploration of Mars is the study of Mars by spacecraft. Probes sent from Earth beginning in the late 20th century have yielded a dramatic increase in knowledge about the Martian system, focused primarily on understanding its geology and habitability potential.

Engineering interplanetary journeys is very complicated, so the exploration of Mars has experienced a high failure rate, especially in earlier attempts. Roughly two-thirds of all spacecraft destined for Mars failed before completing their missions, and there are some that failed before their observations could begin. However, missions have also met with unexpected levels of success, such as the twin Mars Exploration Rovers operating for years beyond their original mission specifications.

As of 24 September 2014, there are two scientific rovers on the surface of Mars beaming signals back to Earth (Opportunity of the Mars Exploration Rover mission, and Curiosity of the Mars Science Laboratory mission), and five orbiters currently surveying the planet: Mars Odyssey, Mars Express, Mars Reconnaissance Orbiter, Mars Orbiter Mission and MAVEN.

To date, no sample return missions have been attempted for Mars, and one attempted return mission for Mars' moon Phobos (Fobos-Grunt) has failed.

On 24 January 2014, NASA reported that current studies on the planet Mars by the Curiosity and Opportunity rovers will now be searching for evidence of ancient life, including a biosphere based on autotrophic, chemotrophic and/or chemolithoautotrophic microorganisms, as well as ancient water, including fluvio-lacustrine environments (plains related to ancient rivers or lakes) that may have been habitable.[2][3][4][5] The search for evidence of habitability, taphonomy (related to fossils), and organic carbon on the planet Mars is now a primary NASA objective.[2]

Martian system[edit]

Main articles: Mars, Atmosphere of Mars and Moons of Mars
The landing site of each Mars mission can be seen on this rotating globe.

Mars has long been the subject of human fascination. Early telescopic observations revealed color changes on the surface that were originally attributed to seasonal vegetation as well as apparent linear features that were ascribed to intelligent design. These early and erroneous interpretations led to widespread public interest in Mars. Further telescopic observations found Mars' two moons, Phobos and Deimos, the polar ice caps, and the feature now known as Olympus Mons, the solar system's tallest mountain.[6] These discoveries piqued further interest in the study and exploration of the red planet. Mars is a rocky planet, like Earth, that formed around the same time, yet with only half the diameter of Earth, and a far thinner atmosphere, it has a cold and desert-like surface. It is notable, however, that although the planet has only one quarter of the surface area of the Earth, it has about the same land area, since only one quarter of the surface area of the Earth is land.

Launch windows[edit]

Opportunities 2013-2020[7]
Year Launch Spacecraft (launched or planned)
2013 Nov 2013 MAVEN, Mars Orbiter Mission
2016 Jan 2016 – Apr 2016 InSight, ExoMars TGO
2018 Apr 2018 – May 2018 ExoMars rover
2020 Jul 2020 – Sep 2020 Mars 2020

The minimum-energy launch windows for a Martian expedition occur at intervals of approximately two years and two months, i.e. 780 days (the planet's synodic period with respect to Earth).[8] In addition, the lowest available transfer energy varies on a roughly 16-year cycle.[8] For example, there was a minimum in the 1969 and 1971 launch windows, rising to a peak in the late 1970s, and hitting another low in 1986 and 1988.[8]

Past and current missions[edit]

Launches to Mars
Decade
1960s
13
1970s
11
1980s
2
1990s
8
2000s
8
2010s
4
Martian sunset by Spirit rover, 2005
North polar view by Phoenix lander, 2008

Starting in 1960 the Soviets launched a series of probes to Mars including the intended first flybys and hard (impact) landing (Mars 1962B).[9] The first successful fly-by of Mars was on July 14–15, 1965, by NASA's Mariner 4.[10] On November 14, 1971 Mariner 9 became the first space probe to orbit another planet when it entered into orbit around Mars.[11] The amount of data returned by probes increased dramatically as technology improved.[9]

The first to contact the surface were two Soviet probes: Mars 2 lander on November 27 and Mars 3 lander on December 2, 1971—Mars 2 failed during descent and Mars 3 about twenty seconds after the first Martian soft landing.[12] Mars 6 failed during descent but did return some corrupted atmospheric data in 1974. [13] The 1975 NASA launches of the Viking program consisted of two orbiters, each with a lander that successfully soft landed in 1976. Viking 1 remained operational for six years, Viking 2 for three. The Viking landers relayed the first color panoramas of Mars[14] and the Viking orbiters mapped the surface so well that the images remain in use.

The Soviet probes Phobos 1 and 2 were sent to Mars in 1988 to study Mars and its two moons, with a focus on Phobos. Phobos 1 lost contact on the way to Mars. Phobos 2, while successfully photographing Mars and Phobos, failed before it was set to release two landers to the surface of Phobos.[15]

Roughly two-thirds of all spacecraft destined for Mars have failed without completing their missions, and it has a reputation as a difficult space exploration target.[16] Missions that ended prematurely after Phobos 1 & 2 (1988) include Mars Observer (Launched in 1992), Mars 96 (1996), Mars Climate Orbiter (1999), Mars Polar Lander with Deep Space 2 (1999), Nozomi (2003), Beagle 2 (2003), and Fobos-Grunt with Yinghuo-1 (2011). (See Probing difficulties section)

Following the 1993 failure of the Mars Observer orbiter, the NASA Mars Global Surveyor achieved Mars orbit in 1997. 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. The NASA Mars Pathfinder, carrying a robotic exploration vehicle Sojourner, landed in the Ares Vallis on Mars in the summer of 1997, returning many images.[17]

Phoenix landed on the north polar region of Mars on May 25, 2008.[18] Its robotic arm dug into the Martian soil and the presence of water ice was confirmed on June 20, 2008.[19][20] The mission concluded on November 10, 2008 after contact was lost.[21] In 2008, the price of transporting material from the surface of Earth to the surface of Mars was approximately US$309,000 per kilogram.[22]

Rosetta came within 250 km of Mars during its 2007 flyby. [23] Dawn flew by Mars in February 2009 for a gravity assist on its way to investigate Vesta and Ceres. [24]

Tharsis Montes Hellas Planitia Olympus Mons Valles Marineris Arabia Terra Amazonis Planitia Elysium Mons Isidis Planitia Terra Cimmeria Argyre Planitia Alba MonsMap of Mars
Interactive imagemap of the global topography of Mars, overlain with locations of Mars landers and rovers. Hover your mouse to see the names of prominent geographic features, and click to link to them. Coloring of the base map indicates relative elevations, based on data from the Mars Orbiter Laser Altimeter on NASA's Mars Global Surveyor. Reds and pinks are higher elevation (+3 km to +8 km); yellow is 0 km; greens and blues are lower elevation (down to −8 km). Whites (>+12 km) and browns (>+8 km) are the highest-most elevations. Axes are latitude and longitude; note poles are not shown.
Spirit (2004) > Spirit
Opportunity (2004) > Opportunity
Pathfinder < Sojourner (1997)
Viking 1 (1976) > Viking 1
Viking 2 (1976) > Viking 2
Phoenix < Phoenix (2008)
Mars 3 < Mars 3 (1971)
Curiosity (2012) > Curiosity
Beagle 2 < Beagle 2 (2003)

Recent missions[edit]

Curiosity‍‍ '​‍s self-portrait on the planet Mars at "Rocknest" (October 31, 2012).

NASA's Mars Odyssey orbiter entered Mars orbit in 2001.[25] Odyssey's Gamma Ray Spectrometer detected significant amounts of hydrogen in the upper metre or so of regolith on Mars. This hydrogen is thought to be contained in large deposits of water ice.[26]

The Mars Express mission of the European Space Agency (ESA) reached Mars in 2003. It carried the Beagle 2 lander, which was not heard from after being released and was declared lost in February 2004. Beagle 2 was located in January 2015 by HiRise camera on NASA’s Mars Reconnaissance Orbiter (MRO) having landed safely but failed to fully deploy its solar panels and antenna.[27][28] In early 2004 the Mars Express Planetary Fourier Spectrometer team announced the orbiter had detected methane in the Martian atmosphere. ESA announced in June 2006 the discovery of aurorae on Mars.[29]

In January 2004, the NASA twin Mars Exploration Rovers named Spirit (MER-A) and Opportunity (MER-B) landed on the surface of Mars. Both 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.[30] Spirit Rover (MER-A) was active until 2010, when it stopped sending data.

On March 10, 2006, the NASA Mars Reconnaissance Orbiter (MRO) probe arrived in orbit to conduct a two-year science survey. The orbiter began mapping the Martian terrain and weather to find suitable landing sites for upcoming lander missions. The MRO snapped the first image of a series of active avalanches near the planet's north pole, scientists said March 3, 2008.[31]

The Mars Science Laboratory mission was launched on November 26, 2011 and it delivered the Curiosity rover, on the surface of Mars on August 6, 2012 UTC. It is larger and more advanced than the Mars Exploration Rovers, with a velocity of up to 90 meters per hour (295 feet per hour).[32] Experiments include a laser chemical sampler that can deduce the make-up of rocks at a distance of 7 meters.[33]

The Indian Space Research Organisation (ISRO) launched its Mars Orbiter Mission (MOM) on November 5, 2013. It was successfully inserted into Mars orbit on 24 September 2014. India's ISRO is the fourth space agency to reach Mars, after the Soviet space program, NASA and ESA.[34] India became the first country to successfully get a spacecraft into the Martian orbit on its maiden attempt.[35]

Journey to Mars - Science, Exploration, Technology.

Overview of missions[edit]

The following entails a brief overview of Mars exploration, oriented towards orbiters and flybys; see also Mars landing and Mars rover.

Early Soviet missions[edit]

Main articles: Mars 1M, Mars 1 and Mars program
Mars 1M spacecraft
1960s[edit]

Between 1960 and 1969, the Soviet Union launched nine probes intended to reach Mars. They all failed: three at launch; three failed to reach near-Earth orbit; one during the burn to put the spacecraft into trans-Mars trajectory; and two during the interplanetary orbit.

The Mars 1M programs (sometimes dubbed Marsnik in Western media) was the first Soviet unmanned spacecraft interplanetary exploration program, which consisted of two flyby probes launched towards Mars in October 1960, Mars 1960A and Mars 1960B (also known as Korabl 4 and Korabl 5 respectively). After launch, the third stage pumps on both launchers were unable to develop enough pressure to commence ignition, so Earth parking orbit was not achieved. The spacecraft reached an altitude of 120 km before reentry.

Mars 1962A was a Mars fly-by mission, launched on October 24, 1962 and Mars 1962B a intended first Mars lander mission, launched in late December of the same year (1962). Both failed from either breaking up as they were going into Earth orbit or having the upper stage explode in orbit during the burn to put the spacecraft into trans-Mars trajectory.

Mars 1 (1962 Beta Nu 1), an automatic interplanetary spacecraft launched to Mars on November 1, 1962, was the first probe of the Soviet Mars probe program to achieve interplanetary orbit. Mars 1 was intended to fly by the planet at a distance of about 11,000 km and take images of the surface as well as send back data on cosmic radiation, micrometeoroid impacts and Mars' magnetic field, radiation environment, atmospheric structure, and possible organic compounds.[36][37] Sixty-one radio transmissions were held, initially at two-day intervals and later at 5 day intervals, from which a large amount of interplanetary data was collected. On 21 March 1963, when the spacecraft was at a distance of 106,760,000 km from Earth, on its way to Mars, communications ceased due to failure of its antenna orientation system.[36][37]

In 1964, both Soviet probe launches, of Zond 1964A on June 4, and Zond 2 on November 30, (part of the Zond program), resulted in failures. Zond 1964A had a failure at launch, while communication was lost with Zond 2 en route to Mars after a mid-course maneuver, in early May 1965.

In 1969, and as part of the Mars probe program, the Soviet Union prepared two identical 5-ton orbiters called M-69, dubbed by NASA as Mars 1969A and Mars 1969B. Both probes were lost in launch-related complications with the newly developed Proton rocket.[38]

1970s[edit]

The USSR intended to have the first artificial satellite of Mars beating the planned American Mariner 8 and Mariner 9 Martian orbiters. In May 1971, one day after Mariner 8 malfunctioned at launch and failed to reach orbit, Cosmos 419 (Mars 1971C), a heavy probe of the Soviet Mars program M-71, also failed to launch. This spacecraft was designed as an orbiter only, while the next two probes of project M-71, Mars 2 and Mars 3, were multipurpose combinations of an orbiter and a lander with small skis-walking rovers that would be the first planet rovers outside the Moon. They were successfully launched in mid-May 1971 and reached Mars about seven months later. On November 27, 1971 the lander of Mars 2 crash-landed due to an on-board computer malfunction and became the first man-made object to reach the surface of Mars. In December 2, 1971 the Mars 3 lander became the first spacecraft to achieve a soft landing, but its transmission was interrupted after 14.5 seconds.

The Mars 2 and 3 orbiters sent back a relatively large volume of data covering the period from December 1971 to March 1972, although transmissions continued through to August. By 22 August 1972, after sending back data and a total of 60 pictures, Mars 2 and 3 concluded their missions. The images and data enabled creation of surface relief maps, and gave information on the Martian gravity and magnetic fields.[39]

In 1973, the Soviet Union sent four more probes to Mars: the Mars 4 and Mars 5 orbiters and the Mars 6 and Mars 7 fly-by/lander combinations. All missions except Mars 7 sent back data, with Mars 5 being most successful. Mars 5 transmitted 60 images before a loss of pressurization in the transmitter housing ended the mission. Mars 6 lander transmitted data during descent, but failed upon impact. Mars 4 flew by the planet at a range of 2200 km returning one swath of pictures and radio occultation data, which constituted the first detection of the nightside ionosphere on Mars.[40] Mars 7 probe separated prematurely from the carrying vehicle due to a problem in the operation of one of the onboard systems (attitude control or retro-rockets) and missed the planet by 1300 km.

Mariner program[edit]

Main articles: Mariner program, Mariner 4, Mariner 6 and 7 and Mariner 9
The first close-up images taken of Mars in 1965 from Mariner 4 show an area about 330 km across by 1200 km from limb to bottom of frame.

In 1964, NASA's Jet Propulsion Laboratory made two attempts at reaching Mars. Mariner 3 and Mariner 4 were identical spacecraft designed to carry out the first flybys of Mars. Mariner 3 was launched on November 5, 1964, but the shroud encasing the spacecraft atop its rocket failed to open properly, dooming the mission. Three weeks later, on November 28, 1964, Mariner 4 was launched successfully on a 7½-month voyage to the red planet.

Mariner 4 flew past Mars on July 14, 1965, providing the first close-up photographs of another planet. The pictures, gradually played back to Earth from a small tape recorder on the probe, showed impact craters. It provided radically more accurate data about the planet; a surface atmospheric pressure of about 1% of Earth's and daytime temperatures of −100 °C (−148 °F) were estimated. No magnetic field[41][42] or Martian radiation belts[43] were detected. The new data meant redesigns for then planned Martian landers, and showed life would have a more difficult time surviving there than previously anticipated.[44][45][46][47]

Mariner Crater, as seen by Mariner 4. The location is Phaethontis quadrangle.

NASA continued the Mariner program with another pair of Mars flyby probes, Mariner 6 and 7. They were sent at the next launch window, and reached the planet in 1969. During the following launch window the Mariner program again suffered the loss of one of a pair of probes. Mariner 9 successfully entered orbit about Mars, the first spacecraft ever to do so, after the launch time failure of its sister ship, Mariner 8. When Mariner 9 reached Mars in 1971, it and two Soviet orbiters (Mars 2 and Mars 3, see Mars probe program below) found that a planet-wide dust storm was in progress. The mission controllers used the time spent waiting for the storm to clear to have the probe rendezvous with, and photograph, Phobos. When the storm cleared sufficiently for Mars' surface to be photographed by Mariner 9, the pictures returned represented a substantial advance over previous missions. These pictures were the first to offer more detailed evidence that liquid water might at one time have flowed on the planetary surface. They also finally discerned the true nature of many Martian albedo features. For example, Nix Olympica was one of only a few features that could be seen during the planetary duststorm, revealing it to be the highest mountain (volcano, to be exact) on any planet in the entire Solar System, and leading to its reclassification as Olympus Mons.

Viking program[edit]

Main articles: Viking program, Viking 1, Viking 2 and Viking spacecraft biological experiments

The Viking program launched Viking 1 and 2 spacecraft to Mars in 1975; The program consisted of two orbiters and two landers – these were the first two spacecraft to successfully land and operate on Mars.

Viking 1 lander site (1st color, July 21, 1976).
Viking 2 lander site (1st color, September 5, 1976).
Viking 2 lander site (September 25, 1977).
(False color image) Frost at Viking 2 site (May 18, 1979).
Martian sunset over Chryse Planitia at Viking 1 site (August 20, 1976).

The primary scientific objectives of the lander mission were to search for biosignatures and observe meteorologic, seismic and magnetic properties of Mars. The results of the biological experiments on board the Viking landers remain inconclusive, with a reanalysis of the Viking data published in 2012 suggesting signs of microbial life on Mars.[48][49]

Flood erosion at Dromore crater.
Tear-drop shaped islands at Oxia Palus.
Streamlined islands in Lunae Palus.
Scour patterns located in Lunae Palus.

The Viking orbiters revealed that large floods of water carved deep valleys, eroded grooves into bedrock, and traveled thousands of kilometers. Areas of branched streams, in the southern hemisphere, suggest that rain once fell.[50][51][52]

Mars Pathfinder[edit]

Sojourner takes Alpha Proton X-ray Spectrometer measurements of the Yogi Rock.
Main articles: Mars Pathfinder and Mars landing

Mars Pathfinder was a U.S. spacecraft that landed a base station with a roving probe on Mars on July 4, 1997. It consisted of a lander and a small 10.6 kilograms (23 lb) wheeled robotic rover named Sojourner, which was the first rover to operate on the surface of Mars.[53][54] In addition to scientific objectives, the Mars Pathfinder mission was also a "proof-of-concept" for various technologies, such as an airbag landing system and automated obstacle avoidance, both later exploited by the Mars Exploration Rovers.

Mars Global Surveyor[edit]

Main article: Mars Global Surveyor
This image from Mars Global Surveyor spans a region about 1500 meters across. Gullies, similar to those formed on Earth, are visible from Newton Basin in Sirenum Terra.
Gullies, similar to those formed on Earth, are visible on this image from Mars Global Surveyor.

After the 1992 failure of NASA's Mars Observer orbiter, NASA retooled and launched Mars Global Surveyor (MGS). This mission was the first successful United States mission, and the first fully successful mission overall, to the red planet in two decades when it launched November 7, 1996, and entered orbit on September 12, 1997. After a year and a half trimming its orbit from a looping ellipse to a circular track around the planet, the spacecraft began its primary mapping mission in March 1999. It observed the planet from a low-altitude, nearly polar orbit over the course of one complete Martian year, the equivalent of nearly two Earth years. Mars Global Surveyor completed its primary mission on January 31, 2001, and completed several extended mission phases.

The mission studied the entire Martian surface, atmosphere, and interior, and returned more data about the red planet than all previous Mars missions combined. The data has been archived and remains available publicly.[55]

This color-coded elevation map was produced from data collected by Mars Global Surveyor.It shows an area around Northern Kasei Valles, showing relationships among Kasei Valles, Bahram Vallis, Vedra Vallis, Maumee Vallis, and Maja Valles. Map location is in Lunae Palus quadrangle and includes parts of Lunae Planum and Chryse Planitia.
A color-coded elevation map produced from data collected by Mars Global Surveyor indicating the result of floods on Mars.

Among key scientific findings, Global Surveyor took pictures of gullies and debris flow features that suggest there may be current sources of liquid water, similar to an aquifer, at or near the surface of the planet. Similar channels on Earth are formed by flowing water, but on Mars the temperature is normally too cold and the atmosphere too thin to sustain liquid water. Nevertheless, many scientists hypothesize that liquid groundwater can sometimes surface on Mars, erode gullies and channels, and pool at the bottom before freezing and evaporating.

Magnetometer readings showed that the planet's magnetic field is not globally generated in the planet's core, but is localized in particular areas of the crust. New temperature data and closeup images of the Martian moon Phobos showed that its surface is composed of powdery material at least 1 metre (3 feet) thick, caused by millions of years of meteoroid impacts. Data from the spacecraft's laser altimeter gave scientists their first 3-D views of Mars' north polar ice cap.

On November 5, 2006 MGS lost contact with Earth.[56] NASA ended efforts to restore communication on January 28, 2007.[57]

Mars Odyssey and Mars Express[edit]

Main articles: 2001 Mars Odyssey and Mars Express

In 2001 NASA's Mars Odyssey orbiter arrived at Mars. Its mission is to use spectrometers and imagers to hunt for evidence of past or present water and volcanic activity on Mars. In 2002, it was announced that the probe's gamma ray spectrometer and neutron spectrometer had detected large amounts of hydrogen, indicating that there are vast deposits of water ice in the upper three meters of Mars' soil within 60° latitude of the south pole.[citation needed]

On June 2, 2003, the European Space Agency's Mars Express set off from Baikonur Cosmodrome to Mars. The Mars Express craft consists of the Mars Express Orbiter and the stationary lander Beagle 2. The lander carried a digging device and the smallest mass spectrometer created to date, as well as a range of other devices, on a robotic arm in order to accurately analyze soil beneath the dusty surface to look for biosignatures and biomolecules.

The orbiter entered Mars orbit on December 25, 2003, and Beagle 2 entered Mars' atmosphere the same day. However, attempts to contact the lander failed. Communications attempts continued throughout January, but Beagle 2 was declared lost in mid-February, and a joint inquiry was launched by the UK and ESA. The Mars Express Orbiter confirmed the presence of water ice and carbon dioxide ice at the planet's south pole, while NASA had previously confirmed their presence at the north pole of Mars.

The lander's fate remained a mystery until it was located intact on the surface of Mars in a series of images from the Mars Reconnaissance Orbiter.[58][59] The images suggest that two of the spacecraft's four solar panels failed to deploy, blocking the spacecraft's communications antenna. Beagle 2 is the first British and first European probe to achieve a soft landing on Mars.

MER and Phoenix[edit]

Main articles: Mars Exploration Rover, Opportunity rover, Spirit rover and Phoenix lander
See also: Mars landing
Polar surface as seen by the Phoenix lander

NASA's Mars Exploration Rover Mission (MER), started in 2003, is an ongoing robotic space mission involving two rovers, Spirit (MER-A) and Opportunity, (MER-B) exploring the Martian surface geology.

The mission's scientific objective is to search for and characterize a wide range of rocks and soils that hold clues to past water activity on Mars. The mission is part of NASA's Mars Exploration Program, which includes three previous successful landers: the two Viking program landers in 1976 and Mars Pathfinder probe in 1997

Mars Reconnaissance Orbiter[edit]

Main article: Mars Reconnaissance Orbiter

Mars Reconnaissance Orbiter is a multipurpose spacecraft designed to conduct reconnaissance and exploration of Mars from orbit. The $720 million USD spacecraft was built by Lockheed Martin under the supervision of the Jet Propulsion Laboratory, launched August 12, 2005, and attained Martian orbit on March 10, 2006.

The MRO contains a host of scientific instruments such as the HiRISE camera, CTX camera, CRISM, and SHARAD. The HiRISE camera is used to analyze Martian landforms, whereas CRISM and SHARAD can detect water, ice, and minerals on and below the surface. Additionally, MRO is paving the way for upcoming generations of spacecraft through daily monitoring of Martian weather and surface conditions, searching for future landing sites, and testing a new telecommunications system that enable it to send and receive information at an unprecedented bitrate, compared to previous Mars spacecraft. Data transfer to and from the spacecraft occurs faster than all previous interplanetary missions combined and allows it to serve as an important relay satellite for other missions.

Rosetta and Dawn swingbys[edit]

Main articles: Rosetta (spacecraft) and Dawn Mission

The ESA Rosetta space probe mission to the comet 67P/Churyumov-Gerasimenko flew within 250 km of Mars on February 25, 2007 in a gravitational slingshot designed to slow and redirect the spacecraft.[60]

The NASA Dawn spacecraft used the gravity of Mars in 2009 to change direction and velocity on its way to Vesta, and tested out Dawn‍‍ '​‍s cameras and other instruments on Mars.[61]

Fobos-Grunt[edit]

Main article: Fobos-Grunt

In November 8, 2011, Russia's Roscosmos launched an ambitious mission called Fobos-Grunt. It consisted of a lander aimed to retrieve a sample back to Earth from Mars' moon Phobos, and place the Chinese Yinghuo-1 probe in Mars' orbit. The Fobos-Grunt mission suffered a complete control and communications failure shortly after launch and was left stranded in low Earth orbit, later falling back to Earth.[62] The Yinghuo-1 satellite and Fobos-Grunt underwent destructive re-entry on January 15, 2012, finally disintegrating over the Pacific Ocean.[63][64][65]

Curiosity rover[edit]

Main articles: Mars Science Laboratory, Curiosity rover and Timeline of Mars Science Laboratory
Curiosity's view of Aeolis Mons ("Mount Sharp") foothills on August 9, 2012 EDT (white balanced image).

The NASA Mars Science Laboratory mission with its rover named Curiosity, was launched on November 26, 2011,[66][67] and landed on Mars on August 6, 2012 on Aeolis Palus in Gale Crater. The rover carries instruments designed to look for past or present conditions relevant to the past or present habitability of Mars.[68][69][70][71]

MAVEN[edit]

NASA's MAVEN is an orbiter mission to study the upper atmosphere of Mars.[72] It will also serve as a communications relay satellite for robotic landers and rovers on the surface of Mars. MAVEN was launched 18 November 2013 and reached Mars on 22 September 2014.

Mars Orbiter Mission[edit]

The Mars Orbiter Mission, also called Mangalyaan, was launched on 5 November 2013 by the Indian Space Research Organisation (ISRO).[73] It was successfully inserted into Martian orbit on 24 September 2014. The mission is a technology demonstrator, and as secondary objective, it will also study the Martian atmosphere. This is India's first mission to Mars, and with it, ISRO became the fourth space agency to successfully reach Mars after the Soviet Union, NASA (USA) and ESA (Europe). It also made India the first country to reach Mars orbit on its first attempt and also the first Asian country to successfully send an orbiter to Mars. It was completed in a record low budget of $71 million,[74][75] making it the least-expensive Mars mission to date.[76]

Future missions[edit]

See also: Mars sample return mission
Proposals
  • The Finnish-Russian MetNet concept would, if implemented in 2015, use multiple small meteorological stations on Mars to establish a widespread observation network to investigate the planet's atmospheric structure, physics and meteorology.[90] The MetNet precursor or demonstrator was considered for a piggyback launch on Fobos-Grunt,[91] and on the two proposed to fly on the 2016 and 2018 ExoMars spacecraft.[90]
  • The Mars-Grunt is a Russian mission concept to bring a sample of Martian soil to Earth.[92]
  • A ESA-NASA team produced a three-launch architecture concept for a Mars sample return, which uses a rover to cache small samples, a Mars ascent stage to send it into orbit, and an orbiter to rendezvous with it above Mars and take it to Earth.[93] Solar-electric propulsion could allow a one launch sample return instead of three.[94]
  • The Mars Scout Program's SCIM would involve a probe grazing the upper atmosphere of Mars to collect dust and air for return to Earth.[95]
  • The United Arab Emirates announced that the first mission of its space agency will be to send an orbiter to Mars, the Mars Hope, by 2020.[96][97]
  • On 10 Nov 2014, China unveiled a prototype model of a Mars rover based on its lunar rover Yutu at an annual air show at Zhuhai. The CASC also said that a mission including an orbiter, lander and the rover will be sent before 2020.[98]

Other future mission concepts include polar probes, Martian aircraft and a network of small meteorological stations.[93] Longterm areas of study may include Martian lava tubes, resource utilization, and electronic charge carriers in rocks.[99][100] Micromissions are another possibility, such as piggybacking a small spacecraft on an Ariane 5 rocket and using a lunar gravity assist to get to Mars.[101]

Human mission proposals[edit]

Concept for NASA Design Reference Mission Architecture 5.0 (2009)
Main article: Human mission to Mars

Many people have long advocated a human mission to Mars as the next logical step for a human space program after lunar exploration. Aside from the prestige such a mission would bring, advocates argue that humans would easily be able to outperform robotic explorers, justifying the expense. Aerospace engineer Bob Zubrin is one of the proponents of such missions. Some critics contend unmanned robots can perform better than humans at a fraction of the expense. If life exists on Mars, a human mission could contaminate it by introducing earthly microbes, so robotic exploration would be preferable.[102] A list of hypothetical or proposed human Mars missions is located at human mission to Mars. See also, colonization of Mars.

ESA[edit]

The ESA has plans to land humans on Mars between 2030 and 2035.[103] This will be preceded by successively larger probes, starting with the launch of the ExoMars probe[103] and a planned joint NASA–ESA Mars sample return mission.[104]

NASA[edit]

Artistic simulated photo looking out a portal spacecraft coming for a Mars landing

Human exploration by the United States was identified as a long-term goal in the Vision for Space Exploration announced in 2004 by then US President George W. Bush.[105] The planned Orion spacecraft would be used to send a human expedition to Earth's moon by 2020 as a stepping stone to a Mars expedition. On September 28, 2007, NASA administrator Michael D. Griffin stated that NASA aims to put a person on Mars by 2037.[106]

On December 2, 2014, NASA's Advanced Human Exploration Systems and Operations Mission Director Jason Crusan and Deputy Associate Administrator for Programs James Reuthner announced tentative support for the Boeing "Affordable Mars Mission Design" including radiation shielding, centrifugal artificial gravity, in-transit consumable resupply, and a lander which can return.[107][108] Reuthner suggested that if adequate funding was forthcoming, the proposed mission would be expected in the early 2030s.[109]

On October 8, 2015, NASA published its official plan for human exploration and colonization of Mars. The plan operates through three distinct phases leading up to fully sustained colonization.[110] The first stage, already underway, is the "Earth Reliant" phase. This phase continues utilizing the International Space Station until 2024; validating deep space technologies and studying the effects of long duration space missions on the human body. The second stage, "Proving Ground," moves away from Earth reliance and ventures into cislunar space for most of its tasks. This is when NASA plans to capture an asteroid (planned for 2020), test deep space habitation facilities, and validate capabilities required for human exploration of Mars. Finally, phase three is the transition to independence from Earth resources. The "Earth Independent" phase includes long term missions on the lunar surface which leverage surface habitats that only require routine maintenance, and the harvesting of Martian resources for fuel, water, and building materials. NASA is still aiming for human missions to Mars in in the 2030s, though Earth independence could take decades longer.[111]

Zubrin[edit]

Mars Direct, a low-cost human mission proposed by Robert Zubrin, founder of the Mars Society, would use heavy-lift Saturn V class rockets, such as the Ares V, to skip orbital construction, LEO rendezvous, and lunar fuel depots. A modified proposal, called "Mars to Stay", involves not returning the first immigrant explorers immediately, if ever (see Colonization of Mars).[105][106][112][112] [113]

Probing difficulties[edit]

Deep Space 2 technology
Further information: Phobos 1, Mars Observer, Mars 96, Nozomi (probe), Mars Climate Orbiter, Mars Polar Lander, Deep Space 2 and Beagle 2

The challenge, complexity and length of Mars missions have lead to many mission failures.[114] The high failure rate of missions launched from Earth attempting to explore Mars is informally called the "Mars Curse" or "Martian Curse".[115] The phrase "Galactic Ghoul"[116] or "Great Galactic Ghoul", referring to a fictitious space monster that subsists on a diet of Mars probes, was coined in 1997 by Time Magazine journalist Donald Neff, and is sometimes facetiously used to "explain" the recurring difficulties.[117][118][119][120]

Two Soviet probes were sent to Mars in 1988 as part of the Phobos program. Phobos 1 operated normally until an expected communications session on 2 September 1988 failed to occur. The problem was traced to a software error, which deactivated attitude thrusters causing the spacecrafts' solar arrays to no longer point at the Sun, depleting Phobos 1 batteries. Phobos 2 operated normally throughout its cruise and Mars orbital insertion phases on January 29, 1989, gathering data on the Sun, interplanetary medium, Mars, and Phobos. Shortly before the final phase of the mission, during which the spacecraft was to approach within 50 m of Phobos' surface and release two landers, one a mobile 'hopper', the other a stationary platform, contact with Phobos 2 was lost. The mission ended when the spacecraft signal failed to be successfully reacquired on March 27, 1989. The cause of the failure was determined to be a malfunction of the on-board computer.[citation needed]

Just a few years later in 1992 Mars Observer, launched by NASA, failed as it approached Mars. Mars 96, an orbiter launched on November 16, 1996 by Russia failed, when the planned second burn of the Block D-2 fourth stage did not occur.[121]

Following the success of Global Surveyor and Pathfinder, another spate of failures occurred in 1998 and 1999, with the Japanese Nozomi orbiter and NASA's Mars Climate Orbiter, Mars Polar Lander, and Deep Space 2 penetrators all suffering various fatal errors. Mars Climate Orbiter was noted for mixing up U.S. customary units with metric units, causing the orbiter to burn up while entering Mars' atmosphere.

Timeline of Mars exploration[edit]

Source:[122]

Totals[edit]

Mission type Success rate Total attempts Success Partial success Launch failure Failed en route Failed to orbit/land
Flyby 45% 11 5 0 4 2 0
Orbiter 50% 23 10 2 5 3 3
Lander 53% 15 8 0 0 3 4
Rover 66% 6 4 0 0 0 2
Total 53% 55 27 2 9 8 9
Mars missions by year
Mars mission rates through time
1969/1971 and 1986/1988 are historical minimum energy launch windows to Mars
note: for the purpose of this graph an orbiter carrying a lander is considered two missions

Timeline[edit]

Mission (1960–1969) Launch Arrival at Mars Termination Elements Outcome
Soviet space programme Mars 1M No.1 10 October 1960 10 October 1960 Flyby Launch failure
Soviet space programme Mars 1M No.2 14 October 1960 14 October 1960 Flyby Launch failure
Soviet space programme Mars 2MV-4 No.1 24 October 1962 24 October 1962 Flyby Broke up shortly after launch
Soviet space programme Mars 1 1 November 1962 21 March 1963 Flyby Some data collected, but lost contact before reaching Mars, flyby at approx. 193,000 km
Soviet space programme Mars 2MV-3 No.1 4 November 1962 19 January 1963 Lander Failed to leave Earth's orbit
National Aeronautics and Space Administration, USA Mariner 3 5 November 1964 5 November 1964 Flyby Failure during launch ruined trajectory
National Aeronautics and Space Administration, USA Mariner 4 28 November 1964 14 July 1965 21 December 1967 Flyby Success (21 images returned)[9]
Soviet space programme Zond 2 30 November 1964 May 1965 Flyby Communication lost three months before reaching Mars
National Aeronautics and Space Administration, USA Mariner 6 25 February 1969 31 July 1969 August 1969 Flyby Success
National Aeronautics and Space Administration, USA Mariner 7 27 March 1969 5 August 1969 August 1969 Flyby Success
Soviet space programme Mars 2M No.521 27 March 1969 27 March 1969 Orbiter Launch failure
Soviet space programme Mars 2M No.522 2 April 1969 2 April 1969 Orbiter Launch failure
Mission (1970–1989) Launch Arrival at Mars Termination Elements Outcome
National Aeronautics and Space Administration, USA Mariner 8 8 May 1971 8 May 1971 Orbiter Launch failure
Soviet space programme Kosmos 419 10 May 1971 12 May 1971 Orbiter Launch failure
National Aeronautics and Space Administration, USA Mariner 9 30 May 1971 13 November 1971 27 October 1972 Orbiter Success (first successful orbit)
Soviet space programme Mars 2 19 May 1971 27 November 1971 22 August 1972 Orbiter Success
27 November 1971 Lander, rover[53] Crashed on surface of Mars
Soviet space programme Mars 3 28 May 1971 2 December 1971 22 August 1972 Orbiter Success
2 December 1971 Lander, rover[53] Partial success. First successful landing; landed softly but ceased transmission within 15 seconds
Soviet space programme Mars 4 21 July 1973 10 February 1974 10 February 1974 Orbiter Could not enter orbit, made a close flyby
Soviet space programme Mars 5 25 July 1973 2 February 1974 21 February 1974 Orbiter Partial success. Entered orbit and returned data, but failed within 9 days[123]
Soviet space programme Mars 6 5 August 1973 12 March 1974 12 March 1974 Lander Partial success. Data returned during descent but not after landing on Mars
Soviet space programme Mars 7 9 August 1973 9 March 1974 9 March 1974 Lander Landing probe separated prematurely; entered heliocentric orbit
National Aeronautics and Space Administration, USA Viking 1 20 August 1975 20 July 1976 17 August 1980 Orbiter Success
13 November 1982 Lander Success
National Aeronautics and Space Administration, USA Viking 2 9 September 1975 3 September 1976 25 July 1978 Orbiter Success
11 April 1980 Lander Success
Soviet space programme Phobos 1 7 July 1988 2 September 1988 Orbiter Contact lost while en route to Mars[124]
Lander Not deployed
Soviet space programme Phobos 2 12 July 1988 29 January 1989 27 March 1989 Orbiter Partial success: entered orbit and returned some data. Contact lost just before deployment of landers
Landers Not deployed
Mission (1990–1999) Launch Arrival at Mars Termination Elements Outcome
National Aeronautics and Space Administration, USA Mars Observer 25 September 1992 24 August 1993 21 August 1993 Orbiter Lost contact just before arrival
National Aeronautics and Space Administration, USA Mars Global Surveyor 7 November 1996 11 September 1997 5 November 2006 Orbiter Success
Russian Federal Space Agency Mars 96 16 November 1996 17 November 1996 Orbiter, lander, penetrator Launch failure
National Aeronautics and Space Administration, USA Mars Pathfinder 4 December 1996 4 July 1997 27 September 1997 Lander, rover Success
National Space Development Agency of Japan Nozomi (Planet-B) 3 July 1998 9 December 2003 Orbiter Complications while en route; Never entered orbit[125]
National Aeronautics and Space Administration, USA Mars Climate Orbiter 11 December 1998 23 September 1999 23 September 1999 Orbiter Crashed on surface due to metric-imperial mix-up
National Aeronautics and Space Administration, USA Mars Polar Lander 3 January 1999 3 December 1999 3 December 1999 Lander Crash-landed on surface due to improper hardware testing
National Aeronautics and Space Administration, USA Deep Space 2 (DS2) Hard landers
Mission (2000–2009) Launch Arrival at Mars Termination Elements Outcome
National Aeronautics and Space Administration, USA 2001 Mars Odyssey 7 April 2001 24 October 2001 Currently operational Orbiter Success
European Space Agency Mars Express 2 June 2003 25 December 2003 Currently operational Orbiter Success
United Kingdom Beagle 2 6 February 2004 Lander Partial success. Landed safely but failed to fully deploy, blocking access to its radio antennas.[126]
National Aeronautics and Space Administration, USA MER-A Spirit 10 June 2003 4 January 2004 22 March 2011 Rover Success
National Aeronautics and Space Administration, USA MER-B Opportunity 7 July 2003 25 January 2004 Currently operational Rover Success
European Space Agency Rosetta 2 March 2004 25 February 2007 Currently operational Flyby/Gravity assist en route to comet 67P/Churyumov-Gerasimenko Successful Mars flyby.
National Aeronautics and Space Administration, USA Mars Reconnaissance Orbiter 12 August 2005 10 March 2006 Currently operational Orbiter Success
National Aeronautics and Space Administration, USA Phoenix 4 August 2007 25 May 2008 10 November 2008 Lander Success
National Aeronautics and Space Administration, USA Dawn 27 September 2007 17 February 2009 Currently operational Gravity assist to Vesta Success
Mission (2010–2019) Launch Arrival at Mars Termination Elements Outcome
Russian Federal Space Agency Fobos-Grunt 8 November 2011 8 November 2011 Phobos lander, sample return Failed to leave Earth orbit.[127] Fell back to Earth.[128]
China National Space Administration Yinghuo-1 8 November 2011 Orbiter
National Aeronautics and Space Administration, USA MSL Curiosity 26 November 2011 6 August 2012 Currently operational Rover Success
Indian Space Research Organisation Mars Orbiter Mission 5 November 2013 24 September 2014 Currently operational Orbiter In orbit and operational[129]
National Aeronautics and Space Administration, USA MAVEN 18 November 2013 22 September 2014 Currently operational Orbiter In orbit and operational [73]

Planned missions[edit]

Name Estimated
launch		 Elements Notes
National Aeronautics and Space Administration, USA InSight March 2016 Lander Study interior structure of Mars.
National Aeronautics and Space Administration, USA MarCO 2 probes, flyby To provide telemetry during atmospheric entry and landing.
European Space Agency Russian Federal Space Agency ExoMars TGO March 14th, 2016 Orbiter Mapping methane sources on Mars.
European Space Agency Schiaparelli lander Atmospheric measurements and testing of technology.
Russian Federal Space Agency ExoMars Surface Platform May 2018 Lander Meteorological tests, and deployment of rover.
European Space Agency Russian Federal Space Agency ExoMars Rover Rover Search for the existence of past or present life on Mars.
National Aeronautics and Space Administration, USA Mars 2020 2020 Rover Astrobiology objectives; rover is based on the Curiosity rover.[130]
Emirates_Institution_for_Advanced_Science_and_Technology, UAE Mars Hope 2020 Orbiter Atmospheric studies; would become the first Arab probe to Mars.[97]

Proposals under study[edit]

Name Estimated
launch		 Elements Notes
Finnish Meteorological Institute MetNet precursor 2015 or later[90] Single impact lander test Precursor for multi-lander network.[131]
Finnish Meteorological Institute MetNet after precursor[90] Multi-lander network Simultaneous meteorological measurements at multiple locations.[90][131]
National Aeronautics and Space Administration, USA Mars Geyser Hopper 2016 Lander Would have the ability to fly or "hop" at least twice from its landed location to reposition itself close to a CO2 geyser site.
Canada Northern Light 2018 Lander, rover Mission designed by Canadian organisations and Thoth Technology Inc.[132]
Indian Space Research Organisation Mangalyaan 2 2018-2020[133] Orbiter, lander Mars orbiter and lander launched by a GSLV launcher.[84][134]
National Aeronautics and Space Administration, USA Icebreaker Life 2018 or 2020 Stationary lander Based on the 2008 Phoenix lander, would perform astrobiology tests on sub-surface ice.[135]
National Aeronautics and Space Administration, USA PADME 2020 Orbiter Would study Phobos and Deimos [136][137]
China Chinese mission 2020 Orbiter, rover [138][139]
Netherlands Mars One Demo 2020 Lander The first demonstration is proposed for launch in 2016.[140][141][dated info]
Netherlands Mars One ComSat 2020 Orbiter Communications satellite.
United States Inspiration Mars Foundation 2021 Manned flyby Private mission to send two humans around Mars on a free return trajectory, without landing.[142]
Japan Aerospace Exploration Agency Martian Moon Sample Return 2021 Lander, sample return Sample return from either Phobos or Deimos.[143][144]
United States Red Dragon 2022 Lander Falcon Heavy rocket with a Dragon capsule; would look for biosignatures.[145][146]
European Space Agency Network 2022 3 landers Meteorological network concept.[147]
European Space Agency Phootprint[148] 2022 Lander and ascent stage Mars moon sample return mission.[147]
United States Mars 2022 2022 Orbiter[149] Communications relay
Netherlands Mars One Rover 2022 Rover Rover to select location for colony.[150]
Russian Federal Space Agency Fobos-Grunt (repeat mission) 2024 Lander, ascent stage Phobos sample return.[151]
Netherlands Mars One 2024 5 landers, rover Two living units, two life support units and a supply units, with a second rover.[150]
Netherlands Mars One 2026 Manned mission Colony.[150]
Netherlands Mars One "Team Two" 2028 Manned mission Four more colonists.[150]
Japan Aerospace Exploration Agency MELOS 2020s rover Version 2 includes a rover and maybe a small aircraft[152]
Russian Federal Space Agency Mars-Grunt 2020s Orbiter, lander, ascent stage Single launch Mars sample return.
National Aeronautics and Space Administration, USA BOLD 2020s 6 landers The Biological Oxidant and Life Detection would perform astrobiology tests on sub-surface soil.[153][154]

Undeveloped concepts[edit]

  • Mars 4NM and Mars 5NM – projects intended by the Soviet Union for heavy Marsokhod (in 1973 according to initial plan of 1970) and Mars sample return (planned for 1975) missions by launching on N1 (rocket) that has never flown successfully.[155]
  • Mars 5M (Mars-79) – double-launching Soviet sample return mission planned to 1979 but cancelled due to complexity and technical problems
  • Vesta - the multiaimed Soviet mission, developed in cooperation with European countries for realisation in 1991–1994 but canceled due to the Soviet Union disbanding, included the flyby of Mars with delivering the aerostat and small landers or penetrators followed by flubys of 1 Ceres or 4 Vesta and some other asteroids with impact of penetrator on the one of them.
  • Voyager-Mars – USA, 1970s – Two orbiters and two landers, launched by a single Saturn V rocket.
  • Mars Aerostat – Russian/French balloon part for cancelled Vesta mission and then for failed Mars 96 mission,[156] originally planned for the 1992 launch window, postponed to 1994 and then to 1996 before being cancelled.[157]
  • Mars Environmental Survey – set of 16 landers planned for 1999–2009
  • Mars-98 – Russian mission including an orbiter, lander, and rover, planned for 1998 launch opportunity as repeat of failured Mars 96 mission and cancelled due to lack of funding
  • Mars Surveyor 2001 Lander – October 2001 – Mars lander (refurbished, became Phoenix lander)
  • Beagle 3 – 2009 British lander mission meant to search for life, past or present.
  • NetLander – 2007 or 2009 – Mars netlanders
  • Mars Telecommunications Orbiter – September 2009 – Mars orbiter for telecommunications
  • Sky-Sailor – 2014 – Plane developed by Switzerland to take detailed pictures of Mars surface
  • Mars Astrobiology Explorer-Cacher – 2018 rover
  • Kitty Hawk – Mars airplane micromission, proposed for December 17, 2003, the centennial of the Wright brothers' first flight.[158] Its funding was eventually given to the 2003 Mars Network project.[159]
  • Tumbleweed rover.[160]

See also[edit]

Portal icon Mars portal
Portal icon Spaceflight portal
Portal icon Robotics portal
Mars
General

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Further reading[edit]

  • Mars – A Warmer, Wetter Planet by Jeffrey S. Kargel (published July 2004; ISBN 978-1-85233-568-7)
  • The Compact NASA Atlas of the Solar System by Ronald Greeley and Raymond Batson (published January 2002; ISBN 0-521-80633-X)
  • Mars: The NASA Mission Reports / edited by Robert Godwin (2000) ISBN 1-896522-62-9

External links[edit]

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