List of objects at Lagrange points


This is a list of known objects which occupy, have occupied, or are planned to occupy any of the five Lagrange points of two-body systems in space.
[Image:Lagrange very massive.svg|right|thumb|300px|A diagram showing the five Lagrange points in a two-body system]

Sun–Earth Lagrange points

Sun–Earth L1

is the Lagrange point located approximately 1.5 million kilometers from Earth towards the Sun.

Past probes

Present probes

Planned probes

Sun–Earth L2

is the Lagrange point located approximately 1.5 million kilometers from Earth in the direction opposite the Sun. Spacecraft at the Sun–Earth L2 point are in a Lissajous orbit until decommissioned, when they are sent into a heliocentric graveyard orbit.

Past probes

Present probes

Planned probes

Cancelled probes

Sun–Earth L3

is the Sun–Earth Lagrange point located on the side of the Sun opposite Earth, slightly outside the Earth's orbit. Direct communication with spacecraft in this position is blocked by the Sun.
  • There are no known objects in this orbital location.

Sun–Earth L4

is the Sun–Earth Lagrange point located close to the Earth's orbit 60° ahead of Earth.
  • Asteroid is the first discovered tadpole orbit companion to Earth, orbiting ; like Earth, its mean distance to the Sun is about one astronomical unit.
  • Asteroid is the second Earth trojan, confirmed in November 2021, oscillating around in a tadpole orbit and expected to remain there for at least 4000 years, until destabilized by Venus.
  • STEREO A made its closest pass to in September 2009, on its orbit around the Sun, slightly faster than Earth.
  • OSIRIS-REx passed near the L4 point and performed a survey for asteroids between 9 and 20 February 2017.

Sun–Earth L5

, or Earth-trailing orbit, is the Sun–Earth Lagrange point located close to the Earth's orbit 60° behind Earth.
  • Asteroid, in a horseshoe companion orbit with Earth, is currently proximal to but at a high inclination.
  • STEREO B made its closest pass to in October 2009, on its orbit around the Sun, slightly slower than Earth.
  • The Spitzer Space Telescope is in an Earth-trailing heliocentric orbit drifting away c. 0.1 AU per year. In c. 2013–15 it has passed in its orbit.
  • Hayabusa2 passed near during the spring of 2017, and imaged the surrounding area to search for Earth trojans on 18 April 2018.

Planned

Earth–Moon Lagrange points

Earth–Moon L2

Earth–Moon L4 and L5

  • Kordylewski clouds
  • Future location of TDRS-style communication satellites to support satellite and further regions on the Moon.

Past probes

  • Hiten was the first spacecraft to demonstrate a low energy trajectory, passing by and to achieve lunar orbit at a very low fuel expense, compared to usual orbital techniques. Hiten did not find any conclusive increase in dust density at Lagrange points.

Proposed objects

Sun–Mars Lagrange points

Sun–Mars L1

Proposed objects

Sun–Mars L4 and L5

Asteroids in the and Sun–Mars Lagrangian points are sometimes called Mars trojans, with a lower-case t, as "Trojan asteroid" was originally defined as a term for Lagrangian asteroids of Jupiter. They may also be called ''Mars Lagrangian asteroids.''

L5

Source: Minor Planet Center

Sun–Ceres Lagrange points

Sun–Jupiter Lagrange points

Asteroids in the and Sun–Jupiter Lagrangian points are known as Jupiter Trojan asteroids or simply Trojan asteroids.

L4

L5

L4 and L5

Saturn–Tethys Lagrange points

L4

L5

Saturn–Dione Lagrange points

L4

L5

Sun–Uranus Lagrange points

L3

L4

*

Sun–Neptune Lagrange points


Minor planets in the and Sun–Neptune Lagrangian points are called Neptune trojans, with a lower-case t, as "Trojan asteroid" was originally defined as a term for Lagrangian asteroids of Jupiter.
Data from: Minor Planet Center

L4

*

L5

*

Tables of missions

Color key:

Future and proposed missions

MissionLagrangian pointAgencyDescription
"Lunar Far-Side Communication Satellites"Earth–Moon NASAProposed in 1968 for communications on the far side of the Moon during the Apollo program,
mainly to enable an Apollo landing on the far side—neither the satellites nor the landing were ever realized.
Space colonization and manufacturingEarth–Moon or —First proposed in 1974 by Gerard K. O'Neill and subsequently advocated by the L5 Society.
DESTINY+Earth–Moon JAXAJAXA "Medium-Sized Focused Mission"; launch planned for 2025.
Exploration Gateway PlatformEarth–Moon NASAProposed in 2011.
Nancy Grace Roman Space Telescope Sun–Earth NASA, USDOELaunch planned for 2026.
LiteBIRDSun–Earth JAXA, NASAJAXA's next "Strategic Large Mission"; launch planned for 2032.
Planetary Transits and Oscillations of stars Sun–Earth ESAPlanned for launch in 2026 for an initial six-year mission.
Space Infrared Telescope for Cosmology
and Astrophysics 		Sun–Earth JAXA, ESA, SRON, awaiting approval from both Japanese and European side, launch proposed for 2032.
Advanced Telescope for High Energy Astrophysics
Sun–Earth ESALaunch planned for 2035.
ESA VigilSun–Earth ESAObservatory for early warning of increased solar activity. Launch planned for 2029.
Sun ChaserSun–Earth —Observatory for early warning of solar particle events. Early proposal phase.
Spektr-MSun–Earth RoscosmosPossible launch after 2030.