A planned 1974 probe, Pioneer H, on display in a museum.

Some fifteen space probes are operational as of February 2016.

A space probe is a robotic spacecraft that leaves Earth orbit and explores space.[1] It may approach the Moon; enter interplanetary space; flyby, orbit, or land on other planetary bodies; or approach interstellar space.

See List of active Solar System probes for a list of active probes; the space agencies of the USSR (now Russia and Ukraine), the United States, the European Union, Japan, China and India have in the aggregate launched probes to several planets and moons of the Solar System as well as to a number of asteroids and comets. Approximately fifteen missions are currently operational.[2]

Interplanetary trajectories[edit | edit source]

Once a probe has left the vicinity of Earth, its trajectory will likely take it along an orbit around the Sun similar to the Earth's orbit. To reach another planet, the simplest practical method is a Hohmann transfer orbit. More complex techniques, such as gravitational slingshots, can be more fuel-efficient, though they may require the probe to spend more time in transit. Some high Delta-V missions (such as those with high inclination changes) can only be performed, within the limits of modern propulsion, using gravitational slingshots. A technique using very little propulsion, but requiring a considerable amount of time, is to follow a trajectory on the Interplanetary Transport Network.[3]

Some notable probes[edit | edit source]

Luna 9[edit | edit source]

First man-made object to soft land on the Moon, or any other extra terrestrial surface.[4]

Luna 3[edit | edit source]

First mission to photograph the far side of the Moon, launched in 1959.

Luna 16[edit | edit source]

First robotic sample return probe from the Moon.

Lunokhod 1[edit | edit source]

First rover on Moon. It was sent to the Moon on November 10, 1970.

Mariner 10[edit | edit source]

First probe to Mercury.

Venera 4[edit | edit source]

First successful in-place analysis of another planet. It may have also been the first space probe to impact the surface of another planet, although it is unclear whether it reached Venus' surface.[5]

Venera 7[edit | edit source]

The Venera 7 probe was the first spacecraft to successfully soft land on another planet (Venus) and to transmit data from there back to Earth.

Mariner 9[edit | edit source]

Upon its arrival at Mars on November 13, 1971, Mariner 9 became the first space probe to maintain orbit around another planet.[6]

The Huygens landing site on Titan

Mars 3[edit | edit source]

First soft landing on Mars (between 1960 and 1973).[citation needed] Although, the spacecraft failed shortly after landing.

Sojourner[edit | edit source]

First successful rover on Mars.[7]

Spirit and Opportunity[edit | edit source]

The Mars Exploration Rovers, Spirit and Opportunity surface and geology, and searched for clues to past water activity on Mars. They were each launched in 2003 and landed in 2004. Communication with Spirit stopped on sol 2210 (March 22, 2010).[8][9] JPL continued to attempt to regain contact until May 24, 2011, when NASA announced that efforts to communicate with the unresponsive rover had ended.[10][11][12] Opportunity arrived at Endeavour crater on 9 August 2011, at a landmark called Spirit Point named after its rover twin, after traversing 13 miles from Victoria crater, over a three-year period.[13] As of January 26, 2016, Opportunity has lasted for more than twelve years on Mars — although the rovers were intended to last only three months.

Halley Armada[edit | edit source]

The first dedicated missions to a comet; in this case, to Halley's Comet during its 1985–86 journey through the inner Solar System. It was also the first massive international coordination of space probes on an interplanetary mission, with probes specifically launched by the Soviet (now Russian) Space Agency, European Space Agency, and Japan's ISAS (now integrated with NASDA to JAXA).

ICE[edit | edit source]

Original a solar observatory in the International Sun-Earth Explorer series, it was sent into solar orbit to make the first close observations of a comet, Comet Giacobini-Zinner, in 1985 as a prelude to studies of Halley's Comet.

Vega[edit | edit source]

Two Russian/French spacecraft. They dropped landers and balloons (first weather balloons deployed on another planet) at Venus before their rendezvous with Halley's Comet.

Sakigake[edit | edit source]

This Japanese probe was the first non-US, non-Soviet interplanetary probe.[citation needed]

Suisei[edit | edit source]

A second Japanese probe, it made ultraviolet wavelength observations of the comet.[Clarification needed]

Giotto[edit | edit source]

The first space probe to penetrate a comet's coma and take close-up images of its nucleus.

Genesis[edit | edit source]

First solar wind sample return probe from sun-earth L1.[citation needed]

Stardust[edit | edit source]

First sample return probe from a comet tail.

NEAR Shoemaker[edit | edit source]

First probe to land on an asteroid.

Hayabusa[edit | edit source]

First sample return probe to launch from an asteroid.

Rosetta[edit | edit source]

The Rosetta space probe has flown by two asteroids and is aiming to rendezvous and explore comet 67P/Churyumov-Gerasimenko. It rendezvoused with the comet in November 2014.[14]

Pioneer 10[edit | edit source]

First probe to Jupiter. Radio communications were lost with Pioneer 10 on January 23, 2003, because of the loss of electric power for its radio transmitter, with the probe at a distance of 12 billion kilometers (80 AU) from Earth.

Pioneer 11[edit | edit source]

First probe to fly by two planets and first probe to Saturn. (Communications were lost due to power constraints and vast distance.)

Voyager 1[edit | edit source]

Voyager 1 is a 733-kilogram probe launched September 5, 1977. It is currently still operational, making it the longest-lasting mission of the U.S. National Aeronautics and Space Administration (NASA). It visited Jupiter and Saturn and was the first probe to provide detailed images of the moons of these planets.

Voyager 1 is the farthest human-made object from Earth, traveling away from both the Earth and the Sun at a relatively faster speed than any other probe.[15] As of September 12, 2013, Voyager 1 is about 12 billion miles from the Sun.[16]

On August 25, 2012, Voyager 1 became the first human made object to enter interstellar space.[17] Voyager 1 has not had a functioning plasma sensor since 1980, but a solar flare in 2012 allowed scientists from NASA to measure vibrations of the plasma surrounding the craft. The vibrations allowed scientists to measure the plasma to be much denser than measurements taken in the far layers of our heliosphere, thus concluding the craft had broken beyond the heliopause.

Voyager 2[edit | edit source]

Voyager 2 was the first probe to complete the Planetary Grand Tour of the gas giants, and the first probe to visit Uranus and Neptune. Voyager 2 is the second-farthest human-made object from Earth, next to Voyager 1 at a distance of 101.2 AU as of July 11, 2013.

Cassini-Huygens[edit | edit source]

Launched on October 15, 1997. Significantly expanded our knowledge of Saturn's ringed system. The lander, Huygens, landed on Titan on January 14, 2005.[18]

New Horizons[edit | edit source]

First probe to be launched to Pluto. Launched on 19 January 2006, it flew by the Pluto–Charon system on 14 July 2015.[19]

Dawn[edit | edit source]

First spacecraft to visit and orbit a protoplanet (4 Vesta), entering orbit on July 16, 2011.[20][21] Entered orbit around dwarf planet Ceres in early 2015. Currently orbiting Ceres as of April 2015.

Juno[edit | edit source]

First probe to Jupiter without atomic battery,[citation needed] launched August 8, 2011.

Chang'e 2[edit | edit source]

First probe to orbit the Moon, visit Sun-Earth L2 Langrangian point and make a flyby of asteroid 4179 Toutatis.[citation needed]

Beyond the Solar System[edit | edit source]

Along with Pioneer 10, Pioneer 11, and its sister space probe Voyager 2, Voyager 1 is now an interstellar probe. Voyager 1 and Voyager 2 have both achieved solar escape velocity, meaning that their trajectories will not return them to the Solar System.[22][23]

Probe imagers[edit | edit source]

Examples of space probe imaging telescope/cameras (focused on visible spectrum).

Name Aperture
cm (in.)
Type Where When
Mars Reconnaissance Orbiter
  1. REDIRECT Template:--

[{Category:Template redirects]]HiRISE || 50 cm (19.7″) || R/C || Mars orbit || 2005

Mars Global Surveyor
  1. REDIRECT Template:--

[{Category:Template redirects]]MOC[24] || 35 cm (13.8″) || R/C || Mars orbit || 1996–2006

New Horizons
  1. REDIRECT Template:--

[{Category:Template redirects]]LORRI[citation needed] || 20.8 cm (8.2″) || R/C || Space (33+ AU from Earth) || 2006

Lunar Reconnaissance Orbiter LROC-NAC[25] 19.5 cm (7.68″) Reflector Lunar orbit 2009
  1. REDIRECT Template:--

[{Category:Template redirects]]ISS-NAC[26] || 19 cm (7.5″) || Reflector || Saturn orbit || 2004

Galileo - Solid State Imager[27] 17.65 cm (6.95″) Reflector Jupiter 1989-2003
Voyager 1/2, ISS-NAC[28] 17.6 cm (6.92″) Catadioptric Space 1977
Mariner 10 - TV Photo Experiment (x2)[29] 15 cm (5.9″) Reflector Space 1973-1975
Deep Space 1
  1. REDIRECT Template:--

[{Category:Template redirects]]MICAS[30] || 10 cm ( 3.94″) || Reflector || Solar orbit || 1998-2001

Voyager 1/2, ISS-WAC[28] 6 cm (2.36″) Lens Space 1977
  1. REDIRECT Template:--

[{Category:Template redirects]]ISS-WAC[26] || 5.7 cm (2.2″) || Lens || Saturn orbit || 2004

MESSENGER MDIS-WAC[31] 3 cm (1.18″) Lens Mercury orbit 2004
MESSENGER MDIS-NAC[32] 2.5 cm (0.98″) R/C Mercury orbit 2004
Dawn Framing Camera (FC1/FC2)[33] 2 cm (0.8″) Lens Asteroid belt 2007

Image forming systems on space probes typically have a multitude of specifications, but aperture can be useful because it constrains the best diffraction limit and light gathering area.[citation needed]

Gallery[edit | edit source]

See also[edit | edit source]


References[edit | edit source]

  1. National Geographic Society. "Space Probes". National Geographic Education. http://education.nationalgeographic.com/education/media/space-probes/. 
  2. http://www.planetary.org/blogs/emily-lakdawalla/2015/12311322-planetary-exploration-timelines.html
  3. "E&S+". E&S+. http://pr.caltech.edu/periodicals/EandS/articles/LXV4/exit.html. 
  4. http://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=1966-006A
  5. http://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=1967-058A
  6. http://marsprogram.jpl.nasa.gov/missions/past/mariner8-9.html
  7. Sojourner (rover)
  8. September 30 – October 05, 2010 Spirit Remains Silent at Troy NASA. 2010-10-05.
  9. A.J.S. Rayl Mars Exploration Rovers Update Planetary Society 30 November 2010
  10. Webster, Guy (25 May 2011). "NASA's Spirit Rover Completes Mission on Mars". NASA. http://www.nasa.gov/mission_pages/mer/news/mer20110525.html. Retrieved 2011-10-12. 
  11. "NASA Concludes Attempts to Contact Mars Rover Spirit". NASA. http://www.jpl.nasa.gov/news/news.cfm?release=2011-156&cid=release_2011-156. Retrieved 25 May 2011. 
  12. Template:Cite news
  13. NASA Mars Rover Arrives at New Site on Martian Surface Jet Propulsion Laboratory, 10 August 2011.
  14. ""Where Comets Emit Dust: Scientists Identify the Active Regions on the Surface of Comets" - ScienceDaily (Apr. 29, 2010)". sciencedaily.com. http://www.sciencedaily.com/releases/2010/04/100426113112.htm. 
  15. "NASA Voyager 1 Encounters New Region in Deep Space". NASA. http://voyager.jpl.nasa.gov/news/voyager_1_new_region.html. 
  16. JPL.NASA.GOV. "Voyager - The Interstellar Mission". nasa.gov. http://voyager.jpl.nasa.gov/. 
  17. "NASA Spacecraft Embarks on Historic Journey Into Interstellar Space". NASA. http://www.nasa.gov/mission_pages/voyager/voyager20130912.html#.Ukixi4brzhg. 
  18. http://sci.esa.int/cassini-huygens/34956-huygens-probe-separation/
  19. Brown, Dwayne; Buckley, Michael; Stothoff, Maria (15 January 2015). "January 15, 2015 Release 15-011 - NASA’s New Horizons Spacecraft Begins First Stages of Pluto Encounter". NASA. http://www.nasa.gov/press/2015/january/nasa-s-new-horizons-spacecraft-begins-first-stages-of-pluto-encounter. Retrieved 15 January 2015. 
  20. "NASA's Dawn Spacecraft Hits Snag on Trip to 2 Asteroids". Space.com. August 15, 2012. http://www.space.com/17119-nasa-dawn-asteroid-spacecraft-vesta.html. Retrieved August 27, 2012. 
  21. "Dawn Gets Extra Time to Explore Vesta". NASA. April 18, 2012. http://www.jpl.nasa.gov/news/news.php?release=2012-107. Retrieved April 24, 2012. 
  22. "Voyager-The Interstellar Mission: Fast Facts". Jet Propulsion Laboratory. http://voyager.jpl.nasa.gov/mission/fastfacts.html. Retrieved November 2, 2013. 
  23. "Voyager-The Interstellar Mission". Jet Propulsion Laboratory. http://voyager.jpl.nasa.gov/mission/interstellar.html. Retrieved November 2, 2013. 
  24. Mars Global Surveyor
  25. eoportal - LRO (Lunar Reconnaissance Orbiter) - LROC
  26. 26.0 26.1 "Cassini Solstice Mission: ISS". Cassini Solstice Mission. http://saturn.jpl.nasa.gov/spacecraft/cassiniorbiterinstruments/instrumentscassiniiss/. 
  27. "Basics of Space Flight Section II. Space Flight Projects". nasa.gov. http://www2.jpl.nasa.gov/basics/bsf12-1.php. 
  28. 28.0 28.1 "Voyager". astronautix.com. http://www.astronautix.com/craft/voyager.htm. 
  29. NASA/NSSDC - Mariner 10 - Television Photography
  30. "Deep Space 1". nasa.gov. http://nmp.jpl.nasa.gov/ds1/. 
  31. Mercury Dual Imaging System (MDIS) - NASA/NSSDC
  33. Sierks, et al. - The Dawn Framing Camera: A Telescope En Route to the Asteroid Belt - MPS/DLR/IDA

Sources[edit | edit source]

Further reading[edit | edit source]

External links[edit | edit source]

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