NASA · flyby active
Lucy
NASA's Lucy is the first mission to the Trojan asteroids that share Jupiter's orbit, visiting more of them than any probe before.
- Launch
- 16 October 2021
- Distance from Earth today
- 921.6 million km6.160 AU · light: 51 min 14 s
- Distance from the Sun today
- 773.8 million km5.172 AU
Live distance from Earth and chart →
Trajectory
Trajectory: JPL Horizons vectors (spacecraft -49) every 3 days, projected onto the ecliptic; compressed distance scale.
Mission timeline
- Launch on an Atlas V from Cape Canaveral
- First Earth gravity assist
- Flyby of asteroid Dinkinesh, which turns out to have a moon
- Second Earth gravity assist
- Flyby of main-belt asteroid Donaldjohanson
- Planned flyby of Trojan asteroid Eurybates
- Planned flyby of the Patroclus–Menoetius binary
Targets: Dinkinesh, Donaldjohanson, Eurybates
About the mission
The Trojans are two swarms of asteroids leading and trailing Jupiter around the Sun, thought to be leftovers from the era when the planets formed. Lucy uses repeated Earth gravity assists to reach both swarms on a single, carefully designed path. On the way it flew past small Dinkinesh in 2023, discovering that it has a contact-binary moon, and past Donaldjohanson in 2025. Encounters with the Trojans start in August 2027 with Eurybates and end in 2033 with the binary pair Patroclus and Menoetius.