# Lucy

*Spacecraft*

A twelve-year tour of the Trojan asteroids that ride ahead of and behind Jupiter in its orbit - leftovers of the outer Solar System, held in place for four billion years. It will visit more asteroids than any spacecraft before it, and is named after the fossil, for the same reason.

| | |
| --- | --- |
| Agency | NASA |
| Launched | 2021-10-16 - still working |
| From the Sun | 747,786,074 km (+488,086 km/d) |
| From the Earth | 835,870,373 km (+2,297,305 km/d) |
| A signal takes | 46 min |
| Travelling at | 9.5 km/s |

Distances and speed are computed from JPL Horizons trajectories and are true of 2026-09-05, changing at the rate given beside each. The interpolation itself is good to a few kilometres; what ages these figures is the date, not the arithmetic.

## Path

A loop round the Sun that Earth flybys keep stretching, out to the two swarms of asteroids that ride ahead of and behind Jupiter. One pass through each, twelve years of it.

## Along the way

- 2022-10-16 — First Earth flyby
- 2023-11-01 — Passed Dinkinesh and found it has a moon of its own
- 2024-12-13 — Second Earth flyby, aimed at the Trojans
- 2025-04-20 — Passed Donaldjohanson in the main belt

## Elsewhere

- On the live map: https://www.orbitalmap.space/?world=solar-system&focus=lucy
- The mission's own page: https://science.nasa.gov/mission/lucy/
- This object as a page: https://www.orbitalmap.space/o/lucy/
- Every object: https://www.orbitalmap.space/o/
- What this site is and what it reads: https://www.orbitalmap.space/llms.txt