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 Sun-Earth 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 Past probes 1.2.2 Present probes 1.2.3 Planned probes 1.2.4 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 2.5 Cancelled objects 3 Sun-Mars Lagrangian points 3.1 L4 3.2 L5 4 Sun-Jupiter 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 Sun-Neptune Lagrangian points 7.1 L4 8 See also 9 References

[edit] Sun-Earth 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.
• NASA's Genesis probe collected solar wind samples at L1 from December 3, 2001 to April 1, 2004, when it returned to Earth.

[edit] Present probes

• GGS WIND
• 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] Past probes

• GEOTAIL

[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 mission

[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
• Spitzer is in an earth-trailing heliocentric orbit drifting away circa 0.1 AU per year. In circa 2013-15 it will pass L₅ in its orbit.

[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.^{[citation needed]}

[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] Cancelled objects

In his book "The High Frontier" Dr. Gerard O'Neill proposed the establishment of gigantic Space Islands in L₅. The inhabitants of the L5 Society should convert Lunar material to huge solar power satellites.

[edit] Sun-Mars Lagrangian points