List of missions to minor planets is a listing of spaceflight missions to minor planets, which are category of astronomical body that excludes planets, moons and comets, but orbit the Sun. Most missions to minor planets have been to asteroids or dwarf planets.
Spacecraft visits to minor planets have mostly been flybys, and have ranged from dedicated missions to incidental flybys and targets of opportunity for spacecraft that have already completed their missions. The first spacecraft to visit an asteroid was Pioneer 10, which flew past an unnamed asteroid on 2 August 1972; a distant incidental encounter while the probe was en route to Jupiter. The first dedicated mission was NEAR Shoemaker , which was launched in February 1996, and entered orbit around 433 Eros in February 2000, having first flown past 253 Mathilde. NEAR was also the first spacecraft to land on an asteroid, surviving what was intended to be an impact with Eros at 20:01 on 12 February 2001 at the planned end of its mission. As a result of its unexpected survival, the spacecraft's mission was extended until 1 March to allow data to be collected from the surface.
Many minor planets are in two rings:
Spacecraft | Launch date [1] | Targeted minor planet | Mission | Outcome | Remarks | Carrier rocket [2] |
---|---|---|---|---|---|---|
Pioneer 10 | 2 March 1972 | Unnamed asteroid [3] | Flyby | — | Distant incidental flyby en route to Jupiter; flyby occurred on 2 August 1972 with closest approach of 8.85 million kilometers (5.5 million miles). | Atlas SLV-3C Centaur-D Star-37E |
307 Nike | — | Distant incidental flyby en route to Jupiter; flyby occurred on 2 December 1972 with closest approach of 8.8 million kilometers (5.4 million miles). | Atlas SLV-3C Centaur-D Star-37E | |||
Galileo | 18 October 1989 | 951 Gaspra | Successful | Incidental flyby en route to Jupiter; flyby occurred on 29 October 1991 with closest approach of 1,604 kilometres (997 mi) at 22:37 UTC [4] | Space Shuttle Atlantis STS-34 / IUS | |
243 Ida | Successful | Incidental flyby en route to Jupiter, discovered Dactyl; flyby occurred on 28 August 1993 with closest approach of 2,410 kilometres (1,500 mi) at 16:51:59 UTC [4] | ||||
Clementine (DSPSE) | 25 January 1994 | 1620 Geographos | Flyby | Spacecraft failure | Attitude control failure; failed to leave geocentric orbit after first phase of mission exploring the Moon. Flyby had been planned for August 1994 [5] | Titan II(23)G |
NEAR Shoemaker (Discovery 1) | 17 February 1996 | 253 Mathilde | Successful | Closest approach 1,212 kilometres (753 mi) at 12:56 UTC on 27 June 1997 [6] | Delta II 7925 | |
433 Eros | Orbiter | Mostly successful | Aborted burn three days before arrival at Eros resulted in failure to enter orbit, instead flew past at 3,827 kilometres (2,378 mi) at 18:41:23 on 23 December 1998. Insertion reattempted successfully on 14 February 2000. Impacted asteroid at 20:01 on 12 February 2001 at end of mission, but survived impact and continued to operate on surface until 1 March. [6] | |||
Cassini–Huygens | 15 October 1997 [1] | 2685 Masursky | Flyby | — | Distant incidental flyby en route to Saturn; closest approach 1.5 million kilometres (0.9 million miles) at 09:58 UTC on 23 January 2000 [7] | Titan IV(401)B Centaur-T [8] |
Deep Space 1 | 24 October 1998 | 4015 Wilson–Harrington [9] | Flyby | Spacecraft failure | Spacecraft was unable to reach the asteroid due to ion engine operation being suspended while a problem with the probe's star tracker was investigated [10] | Delta II 7326 |
9969 Braille | Partial failure | Closest approach 28.3 kilometres (17.6 mi) at 04:46 UTC [10] on 29 July 1999. Intended to pass within 14 kilometres (8.7 mi) but this was not achieved due to a computer failure; poor-quality images returned as a result. [11] Flyby added to mission following loss of ability to reach Wilson–Harrington | ||||
Stardust (Discovery 4) | 7 February 1999 | 5535 Annefrank [12] | Successful | Closest approach of 3,079 kilometres (1,913 mi) at 04:50:20 UTC on 2 November 2002 | Delta II 7426 | |
Hayabusa (MUSES-C) | 9 May 2003 | 25143 Itokawa | Orbiter/lander Sample return | Partial failure | Reached Itokawa on 12 September 2005, landed briefly on 19 and 25 November but sampler failed to operate, missed return window due to communications outage, finally returned to Earth on 13 June 2010 | M-V |
MINERVA | Lander | Failure | Deployed from Hayabusa on 12 November 2005; Accidentally released while Hayabusa was moving away from Itokawa; reached escape velocity and drifted off into heliocentric orbit | |||
Rosetta | 2 March 2004 | 2867 Šteins | Flyby | Successful | Closest approach 800 kilometres (500 mi) on 5 September 2008 | Ariane 5G+ |
21 Lutetia | Successful | Closest approach 3,162 kilometres (1,965 mi) on 10 July 2010 | ||||
67P/Churyumov–Gerasimenko | Lander | Successful | Rendezvous 6 August 2014, orbit on 10 September 2014 Philae(lander) landed on 12 November 2014, Rosetta itself landed on 30 September 2016 | |||
Deep Impact (Discovery 7) | 12 January 2005 | (163249) 2002 GT | Flyby | Spacecraft failure (Extended mission) | Extended mission (EPOXI), flyby was expected in 2020, but communication with the spacecraft was lost in August 2013 | Delta II 7925 |
New Horizons (New Frontiers 1) | 19 January 2006 | 132524 APL | Flyby | — | Incidental flyby en route to Pluto, closest approach 101,867 kilometres (63,297 mi) at 04:05 UTC on 13 June 2006 | Atlas V 551 |
134340 Pluto and its five moons. | Flyby | Successful | Flyby occurred on 14 July 2015 | |||
486958 Arrokoth | Successful | Flyby occurred on 1 January 2019 | ||||
Dawn (Discovery 9) | 27 September 2007 | 4 Vesta | Orbiter | Successful | Orbited Vesta from 16 July 2011 to 5 September 2012, before departing for Ceres | Delta II 7925H |
1 Ceres | Successful | Arrived in 2015 | ||||
Chang'e-2 | 1 October 2010 | 4179 Toutatis | Flyby | Successful | Flyby on 13 December 2012, closest approach 3.2 kilometres (2.0 mi) | Long March 3C |
Hayabusa2 | 3 December 2014 | 162173 Ryugu | Orbiter/lander Sample return | Successful | Arrived in 2018, landed in February and July 2019 Sample returned to Earth on 5 December 2020 UTC | H-IIA 202 |
HIBOU | Lander | Successful | Deployed from Hayabusa2 on 21 September 2018 | |||
OWL | Successful | Deployed from Hayabusa2 on 21 September 2018 | ||||
MINERVA II-2 | Spacecraft failure | Deployed from Hayabusa2 on 2 October 2019; lander failed prior to deployment, but was deployed anyway to observe the effects of gravity on it as it descended to the surface. | ||||
MASCOT | Successful | Deployed from Hayabusa2 on 3 October 2018; operated for 17 hours | ||||
SCI impactor | Impactor | Successful | Deployed from Hayabusa2 on 5 April 2019 | |||
DCAM-3 | Orbiter | Successful | Deployed from Hayabusa2 on 5 April 2019; observed SCI impact | |||
PROCYON | (185851) 2000 DP107 | Flyby | Spacecraft failure | Flyby had been planned for 2016; cancelled due to ion engine failure in heliocentric orbit [13] | ||
OSIRIS-REx (New Frontiers 3) | 8 September 2016 | 101955 Bennu | Orbiter Sample return | Successful | Successfully collected sample of Bennu on 20 October 2020 and is expected to return to Earth on 24 September 2023. | Atlas V 411 |
99942 Apophis | enroute | 8 April 2029. Part of extended mission as OSIRIS-APEx. | ||||
Lucy (Discovery 13) | 16 October 2021 | 152830 Dinkinesh | Flyby | Successful | Closest approach of 425 km (264 mi) at 16:54 UTC on 1 November 2023. | Atlas V 401 |
52246 Donaldjohanson | enroute | 20 April 2025 | ||||
3548 Eurybates | enroute | 12 August 2027 | ||||
15094 Polymele | enroute | 15 September 2027 | ||||
11351 Leucus | enroute | 18 April 2028 | ||||
21900 Orus | enroute | 11 November 2028 | ||||
617 Patroclus | enroute | 2 March 2033 | ||||
DART/LICIACube | 24 November 2021 | Dimorphos | Impactor | Successful | Impacted 23:14 UTC 26 September 2022 | Falcon 9 |
65803 Didymos system | Flyby | Successful | Flyby on 26 September 2022 | |||
NEA Scout | 16 November 2022 | 2020 GE | Flyby | Spacecraft failure | Spacecraft was to perform a series of lunar flybys before targeting asteroid in September 2023, but after launch contact was lost and later the mission was declared as a failure. | SLS Block 1 |
Psyche (Discovery 14) | 13 October 2023 | 16 Psyche | Orbiter | enroute | August 2029 [14] | Falcon Heavy |
Odin (Brokkr-2) | 2024 | undisclosed | Flyby | Planned | Expected to reach its M-type near-Earth target about nine months after launch. [15] [16] [17] [18] | Falcon 9 Block 5 |
Hera | October 2024 | 65803 Didymos | Orbiter | Planned | December 2026 [19] | Ariane 6 |
Tianwen-2 | May 2025 [20] | 469219 Kamoʻoalewa | Orbiter/lander Sample return | Planned | 2026 [21] [22] | Long March 3B |
DESTINY+ | 2025 [23] | 3200 Phaethon | Flyby | Planned | 2029 [24] | Epsilon S |
MBR Explorer | March 2028 [25] | 10253 Westerwald | Flyby | Planned | February 2030 | |
623 Chimaera | Planned | |||||
13294 Rockox | Planned | January 2031 | ||||
(88055) 2000 VA28 | Planned | July 2032 | ||||
(23871) 1998 RC76 | Planned | |||||
(59980) 1999 SG6 | Planned | August 2033 | ||||
269 Justitia | Orbiter/lander | Planned | October 2034 |
Space exploration is the use of astronomy and space technology to explore outer space. While the exploration of space is currently carried out mainly by astronomers with telescopes, its physical exploration is conducted both by uncrewed robotic space probes and human spaceflight. Space exploration, like its classical form astronomy, is one of the main sources for space science.
A gravity assist, gravity assist maneuver, swing-by, or generally a gravitational slingshot in orbital mechanics, is a type of spaceflight flyby which makes use of the relative movement and gravity of a planet or other astronomical object to alter the path and speed of a spacecraft, typically to save propellant and reduce expense.
The Discovery Program is a series of Solar System exploration missions funded by the U.S. National Aeronautics and Space Administration (NASA) through its Planetary Missions Program Office. The cost of each mission is capped at a lower level than missions from NASA's New Frontiers or Flagship Programs. As a result, Discovery missions tend to be more focused on a specific scientific goal rather than serving a general purpose.
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Mariner Mark II was NASA's planned family of uncrewed spacecraft for the exploration of the outer Solar System that were to be developed and operated by JPL between 1980 through the year 2010.
The Comet Rendezvous Asteroid Flyby (CRAF) was a cancelled plan for a NASA-led exploratory mission designed by the Jet Propulsion Laboratory during the mid-to-late 1980s and early 1990s, that planned to send a spacecraft to encounter an asteroid, and then to rendezvous with a comet and fly alongside it for nearly three years. The project was eventually canceled when it went over budget; most of the money still left was redirected to its twin spacecraft, Cassini–Huygens, destined for Saturn, so it could survive Congressional budget cutbacks. Most of CRAF's scientific objectives were later accomplished by the smaller NASA spacecraft Stardust and Deep Impact, and by ESA's flagship Rosetta mission.
Venera 2, also known as 3MV-4 No.4 was a Soviet spacecraft intended to explore Venus. A 3MV-4 spacecraft launched as part of the Venera programme, it failed to return data after flying past Venus.
The New Frontiers program is a series of space exploration missions being conducted by NASA with the purpose of furthering the understanding of the Solar System. The program selects medium-class missions which can provide high science returns.
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The exploration of Saturn has been solely performed by crewless probes. Three missions were flybys, which formed an extended foundation of knowledge about the system. The Cassini–Huygens spacecraft, launched in 1997, was in orbit from 2004 to 2017.
A flyby is a spaceflight operation in which a spacecraft passes in proximity to another body, usually a target of its space exploration mission and/or a source of a gravity assist to impel it towards another target. Spacecraft which are specifically designed for this purpose are known as flyby spacecraft, although the term has also been used in regard to asteroid flybys of Earth for example. Important parameters are the time and distance of closest approach.
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It [pioneer 10] passed within 5.5 million miles of an unnamed 0.5-mile diameter asteroid on Aug. 2