List of objects at Lagrangian points

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This is a list of known objects which have been, are or are planned to occupy any of the five Lagrangian points of two-body systems in space.

Contents 1 Earth-Sun Lagrangian points 1.1 L1 1.1.1 Past probes 1.1.2 Present probes 1.1.3 Planned probes 1.1.4 Cancelled probes 1.2 L2 1.2.1 Present probes 1.2.2 Planned probes 1.2.3 Cancelled probes 1.3 L3 1.4 L4 1.5 L5 2 Earth-Moon Lagrangian points 2.1 L2 2.2 L4 2.3 L5 2.4 L4 and L5 3 Mars-Sun Lagrangian points 3.1 L4 3.2 L5 4 Jupiter-Sun Lagrangian points 4.1 L4 4.2 L5 5 Saturn-Tethys Lagrangian points 5.1 L4 5.2 L5 6 Saturn-Dione Lagrangian points 6.1 L4 6.2 L5 7 Neptune-Sun Lagrangian points 7.1 L4 8 See also 9 References

[edit] Earth-Sun Lagrangian points

[edit] L₁

L₁ is the Lagrangian point located approximately 1,500,000 km towards the Sun away from the Earth.

[edit] Past probes

• International Cometary Explorer, formerly the International Sun-Earth Explorer 3 (ISEE-3), diverted out of L₁ in 1983 for a comet rendezvous mission. Currently in solar orbit, it may be captured in 2014 when it next approaches Earth.
• Genesis, which returned to Earth in September 2004 after collecting solar wind particles for three years. The sample return capsule crash-landed in Tooele County, Utah, when its parachute failed, making its planned airplane-grab recovery impossible. Usable samples were recovered from the capsule anyway, making the mission a partial success.
• WIND, a NASA spacecraft, was launched in November of 1994 in order to study solar wind. The spacecraft's original mission was to orbit the Sun at the L1 Lagrangian point, but this was changed when the SOHO spacecraft was sent to the same location.

[edit] Present probes

• The Solar and Heliospheric Observatory (SOHO)
• The Advanced Composition Explorer (ACE)

[edit] Planned probes

• LISA Pathfinder
• Kuafu

[edit] Cancelled probes

• The Triana satellite, designed to monitor global warming

[edit] L₂

L₂ is the Lagrangian point located approximately 1,500,000 km away from the Earth in the direction opposite the Sun.

[edit] Present probes

• Wilkinson Microwave Anisotropy Probe (WMAP)

[edit] Planned probes

• The joint NASA, ESA and CSA James Webb Space Telescope (JWST), formerly known as the Next Generation Space Telescope (NGST)
• The ESA Herschel Space Observatory
• The ESA Planck Surveyor
• The ESA Gaia probe
• The NASA Terrestrial Planet Finder mission (may be placed in an Earth-trailing orbit instead)
• The ESA Darwin mission

[edit] Cancelled probes

• The ESA Eddington space telescope

[edit] L₃

L₃ is the Lagrangian point located on the side of the Sun opposite the Earth, slightly outside the Earth's orbit.

• There are no known objects in this orbital location.

[edit] L₄

L₄ is the Lagrangian point located close to the Earth's orbit 60° ahead of the Earth.

• Dust clouds ^[1]

[edit] L₅

L₅ is the Lagrangian point located close to the Earth's orbit 60° behind the Earth.

• Dust clouds

[edit] Earth-Moon Lagrangian points

[edit] L₂

• future location of TDRS-derived satellites to facilitate direct communications between Earth and far side of the Moon.

[edit] L₄

• possible Kordylewski clouds

[edit] L₅

• possible Kordylewski clouds

[edit] L₄ and L₅

• future location of TDRS-style communication satellites to support L₂ satellite

[edit] Mars-Sun Lagrangian points