Sun–Earth L2

E59342

Sun–Earth L2 is a gravitationally stable point in space located beyond Earth's orbit where the combined gravity of the Sun and Earth allows spacecraft, such as the James Webb Space Telescope, to maintain a relatively constant position with minimal fuel use.

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Observed surface forms (3)


Statements (47)

Predicate Object
instanceOf Lagrange point
gravitational equilibrium point
advantage continuous view of deep space away from Sun and Earth
reduced fuel consumption for orbit maintenance compared to free heliocentric orbit
relatively constant geometry with Earth and Sun
stable thermal environment for spacecraft
benefitForTelescopes minimal Earth occultation of observed sky
reduced stray light from Earth and Moon
simplified sunshield design
communication continuous line of sight to Earth with high-gain antenna steering
coOrbitsWith Earth
coordinateFrame Sun–Earth rotating frame
directionFromEarth away from the Sun
discoveredBy Joseph-Louis Lagrange
discoveryMethod analytical solution of restricted three-body problem
distanceFromEarth about 0.01 astronomical units
approximately 1.5 million kilometers
field astrodynamics
celestial mechanics
gravitationalInfluence Earth
Sun
illuminationCondition Sun, Earth, and Moon remain on same side of spacecraft
label L2
locatedIn Solar System
surface form: Sun–Earth system
missionDesign spacecraft typically orbit around L2 rather than sit exactly at the point
orbitalPeriod approximately 1 year
orbits Sun
positionType collinear Lagrange point
relatedConcept Lagrange points L1, L3, L4, L5 in Sun–Earth system
relativeTo Earth
Sun
requires station-keeping maneuvers
stabilityAxes stable in rotating frame with active control
unstable along radial direction
stabilityType metastable
typicalOrbit Lissajous orbit
halo orbit
usedBy Euclid spacecraft
Gaia observatory
surface form: Gaia spacecraft

Herschel Space Observatory
James Webb Space Telescope
Planck spacecraft
Spektr-RG observatory
usedFor astrometry
cosmic microwave background observations
cosmology missions
infrared astronomy

Referenced by (8)

Full triples — surface form annotated when it differs from this entity's canonical label.

this entity surface form: Sun–Earth L2 point
Herschel Space Observatory location Sun–Earth L2
NIRCam observatoryLocation Sun–Earth L2
this entity surface form: Sun–Earth L2 point
NIRSpec observatoryLocation Sun–Earth L2
this entity surface form: Sun–Earth L2 point
this entity surface form: Sun–Earth L2 point
Gaia observatory orbitAround Sun–Earth L2
this entity surface form: Sun–Earth L2 Lagrange point
this entity surface form: Sun–Earth L2 halo orbit