List of Mars orbiters

Artist's rendering of NASA's 2001 Mars Odyssey orbiting Mars

The following table is a list of Mars orbiters, consisting of space probes which were launched from Earth and are currently orbiting Mars. As of August 2023, there have been 18 spacecraft missions operating in Mars' orbit, 7 of which are currently active.

History

20th century

Soviet stamp depicting Mars 2

The Soviets' Mars program and the United States' Mariner program became the two first successful space programs that intended to explore Mars through orbiters. Mars 2, Mars 3 and Mariner 9 were all launched into space in May 1971, and all entered Mars’ orbit that same year. NASA's Mariner 9 reached the planet's orbit first on November 14, narrowly beating the Soviet's spacecraft amid the space race, and subsequently became the first spacecraft to orbit another planet.[1]

Contact with all eight Mars orbiters launched during the 20th century has been lost. NASA's four spacecraft are conjectured to remain in Mars' orbit. Mariner 9, Viking 1 and Viking 2 are expected to lower down into the Martian atmosphere by 2022 and either burn up or crash into the planet's surface.[2] Mars Global Surveyor is expected to crash onto the surface of the planet by 2047. The fate of the Soviet's three Mars program orbiters and Phobos 2 remains unclear, but they are still presumed to be in orbit.[3]

In 1999 the Mars Climate Orbiter impacted the Martian atmosphere.

21st century

Artist's rendition of Mars Express as seen by NASA's Mars Global Surveyor
Image of Mars Express in orbit at Mars

2001 Mars Odyssey was launched April 7, 2001 on a Delta II rocket and currently holds the record for the longest-surviving continually active spacecraft in orbit around a planet other than Earth at 23 years and 29 days.[4]

In 2003, the European Space Agency (ESA) launched their first planetary mission with Mars Express to conduct reconnaissance and exploration of Mars from orbit.[5] On 12 August 2005, NASA launched Mars Reconnaissance Orbiter (MRO). As MRO entered orbit in 2006, it joined three other active spacecraft which were in Mars' orbit: Mars Global Surveyor (MGS), Mars Express, and 2001 Mars Odyssey; at the time, this set a record for the most operational spacecraft in the immediate vicinity of Mars. MGS has since ceased to function.

On November 5, 2013, the Mars Orbiter Mission (Mangalyaan-1) was launched by the Indian Space Research Organisation (ISRO) as a "technology demonstrator" project. Its secondary goal is to analyze the Martian atmosphere and topography. The orbiter reached Mars orbit on September 24, 2014. Through this mission, ISRO became the first space agency to succeed in its first attempt at a Mars orbiter. The mission is the first successful Asian interplanetary mission.[6] Ten days after ISRO's launch, NASA launched their seventh Mars orbiter MAVEN to study the Martian atmosphere. Its goals include determining how the planet's atmosphere and water, presumed to have once been substantial, were lost over time.[7]

Fate

After achieving orbit, functional or not, Mars orbiters have been predicted to remain in orbit for a certain amount of time.[8]

  • Viking 1 orbiter, likely to be in orbit as of 2019.[9]
  • Mariner 9 was expected to remain in orbit until approximately 2022, when the spacecraft was projected to enter the Martian atmosphere and either burn up or crash into the planet's surface.[10]
  • Mars Global Surveyor is predicted to orbit until 2046 (50 years after insertion).[11]

Besides decaying to Mars, a collision with a moon or other spacecraft is also a possibility.[12] In March 2017, MAVEN had to change its orbit to avoid colliding with Phobos, and with an increasing number of spacecraft at Mars this risk increases.[13] The Mars Global Surveyor is still being tracked, although it is no longer functioning.[14]

Table of objects

Color legend
Destroyed
Loss of contact
Operational

Note that days active category does not necessarily equate to time in orbit, for example Mars Global Surveyor is expected remain in Mars orbit for 50 years after its arrival.[15] The detection of derelict spacecraft in Mars orbit has some interest due to the minute risk of collision with such a spacecraft. One example of this is a proposal to use the Optical Navigation Camera on the Mars Reconnaissance Orbiter to search for small moons, dust rings, and old orbiters.[16]

Artificial object Agency Launch date Entered orbit Days active Image
Mars 2 Soviet Union Lavochkin 19 May 1971 27 November 1971 269 days
Mars 3 Soviet Union Lavochkin 28 May 1971 2 December 1971 264 days
Mariner 9 United States NASA 30 May 1971 14 November 1971 348 days
Mars 5 Soviet Union Lavochkin 25 July 1973 12 February 1974 16 days
Viking 1 United States NASA 20 August 1975 19 June 1976 1,520 days
Viking 2 United States NASA 9 September 1975 7 August 1976 717 days
Phobos 2 Soviet Union Lavochkin 12 July 1988 29 January 1989 57 days
Mars Global Surveyor United States NASA 7 November 1996 12 September 1997 3,338 days
2001 Mars Odyssey United States NASA 7 April 2001 24 October 2001 8,430 days
Mars Express European Space Agency ESA 2 June 2003 25 December 2003 7,638 days
Mars Reconnaissance Orbiter United States NASA 12 August 2005 10 March 2006 6,832 days
Mars Orbiter Mission
(Mangalyaan) 		India ISRO 5 November 2013 24 September 2014 2,930 days
MAVEN United States NASA 18 November 2013 22 September 2014 3,714 days
ExoMars Trace Gas Orbiter European Space Agency ESA
Russia Roscosmos 		14 March 2016 19 October 2016 2,956 days
Emirates Mars Mission
(Hope) 		United Arab Emirates UAESA 19 July 2020 9 February 2021 1,382 days
Tianwen 1
orbiter 		China CNSA 23 July 2020 10 February 2021 1,381 days
Tianwen 1
Deployable Camera 2 		China CNSA 23 July 2020 10 February 2021 (released on 31 December 2021) <1 day

See also

References

  1. ^ Pyle, Rod (2012). Destination Mars. Prometheus Books. pp. 73–78. ISBN 978-1-61614-589-7. It was the first spacecraft to enter orbit around another world. ... [It] continues to orbit Mars to this day, sailing around the planet deaf and dumb in the cold darkness.
  2. ^ NASA - This Month in NASA History: Mariner 9, November 29, 2011 — Vol. 4, Issue 9
  3. ^ Dunn, Marcia (October 27, 1996). "NASA Takes No Dirty Chances With Mars Rover". Los Angeles Times. Retrieved 2015-08-03. It's expected to orbit Mars for at least 50 years before crashing onto the surface of the planet.
  4. ^ "NASA's Odyssey Spacecraft Sets Exploration Record on Mars". Press Releases. JPL, NASA. 2010-12-15. Retrieved 2015-11-06.
  5. ^ ESA - Mars Express - Mars Express Frequently Asked Questions (FAQs)
  6. ^ "ISRO: Mars Orbiter Mission". isro.gov.in. Archived from the original on 2013-11-09.
  7. ^ Brown, Dwayne; Neal-Jones, Nancy; Zubritsky, Elizabeth (September 21, 2014). "NASA's Newest Mars Mission Spacecraft Enters Orbit around Red Planet". NASA. Retrieved September 22, 2014.
  8. ^ Dunn, Marcia (October 27, 1996). "NASA Takes No Dirty Chances With Mars Rover". Los Angeles Times. Retrieved 2015-08-03. It's expected to orbit Mars for at least 50 years before crashing onto the surface of the planet.
  9. ^ Jefferson, David C; Demcak, Stuart W; Esposito, Pasquale B; Kruizinga, Gerhard L (10–13 August 2009). An Investigation of the Orbital Status of Viking-1 (PDF). AIAA Guidance, Navigation, and Control Conference. Archived from the original (PDF) on 3 January 2017. Retrieved 31 December 2017.
  10. ^ NASA – This Month in NASA History: Mariner 9, November 29, 2011 – Vol. 4, Issue 9
  11. ^ Dunn, Marcia (October 27, 1996). "NASA Takes No Dirty Chances With Mars Rover". Los Angeles Times. Retrieved 2015-08-03. It's expected to orbit Mars for at least 50 years before crashing onto the surface of the planet.
  12. ^ "NASA spacecraft avoids potential collision with Martian moon - SpaceNews.com". SpaceNews.com. 2017-03-03. Retrieved 2017-12-31.
  13. ^ "NASA spacecraft avoids potential collision with Martian moon - SpaceNews.com". SpaceNews.com. 2017-03-03. Retrieved 2017-12-31.
  14. ^ "NASA spacecraft avoids potential collision with Martian moon - SpaceNews.com". SpaceNews.com. 2017-03-03. Retrieved 2017-12-31.
  15. ^ Dunn, Marcia (October 27, 1996). "NASA Takes No Dirty Chances With Mars Rover". Los Angeles Times. Retrieved 2015-08-03. It's expected to orbit Mars for at least 50 years before crashing onto the surface of the planet.
  16. ^ M. Adler, et al. – Use of MRO Optical Navigation Camera .. (2012)