The Lucy logo says "first to the Trojan asteroids. It features an outline of the Lucy skeleton, the spacecraft and Trojan asteroids in the backgorund.

Lucy

The first mission to explore the Jupiter Trojan asteroids.

active Mission

Lucy will explore a record-breaking number of asteroids, flying by three asteroids in the solar system’s main asteroid belt, and by eight Trojan asteroids that share an orbit around the Sun with Jupiter.

Mission Type

Asteroid flybys

Number of Asteroids

11

Launch

Oct. 16, 2021

first flyby

Nov. 1, 2023

Overview

Lucy is the first space mission to explore a diverse population of small bodies known as the Jupiter Trojan
asteroids. These remnants of our early solar system are trapped on stable orbits associated with – but not close to – the giant planet Jupiter. Trojan asteroids orbit in two “swarms” that lead and follow Jupiter in its orbit around the Sun and are thought to be comparable in number to the objects in the main asteroid belt between the orbits of Mars and Jupiter.

Over its 12-year mission, Lucy will explore a record-breaking number of asteroids: it will by two (plus a newly discovered satellite) in the belt of asteroids that circle the Sun between the orbits of Mars and Jupiter, and then eight Trojans, which includes five asteroid targets and the satellites of three of those. Lucy also will fly by Earth three times to get a push from its gravity, making it the first spacecraft to return to the vicinity of Earth from the outer solar system.

Lucy is named for a fossilized skeleton of a human ancestor, which was named for the Beatles song "Lucy in the Sky with Diamonds."

Asteroid
Flyby Date
Dinkinesh (pronounced DIN-ke-nesh) and an
unnamed satellite (discovered during the flyby)
Nov. 1, 2023
DonaldJohanson
April 20, 2025
Eurybates ("yoo-RIB-a-teez" or "you-ri-BAY-teez")
and its satellite Queta ("KEH-tah")
Aug. 12, 2027
Polymele ("pah-li-MEH-lee" or "pah-LIM-ah-lee")
and its unnamed satellite
Sept. 15, 2027
Leucus ("LYOO-kus" or "LOO-kus")
April 18, 2028
Orus ("O-rus")
Nov. 11, 2028
Patroclus ("pa-TROH-klus") and its satellite
Menoetius ("meno-EE-shus" or “meh-NEE-shus”)
March 3, 2033

The Lucy mission is named after the fossilized skeleton of an early hominin (pre-human ancestor) that was found in Ethiopia in 1974 and named “Lucy” by the team of paleoanthropologists who discovered it. And just as the Lucy fossil provided unique insights into human evolution, the Lucy mission promises to expand our knowledge of planetary origins.

Lucy Blog Posts

A team member sits with their back to a large model of the Lucy spacecraft with its large, circular solar panel arrays. Image credit: Lockheed Martin

NASA’s Lucy Spacecraft Completes Asteroid Flyby

The Lucy operations team has confirmed that NASA’s Lucy spacecraft has phoned home after its encounter with the small main belt asteroid, Dinkinesh. 

A graphic illustrating the expected motion of the NASA Lucy spacecraft and its instrument pointing platform (IPP) during the encounter with asteroid Dinkinesh. The yellow, blue, and grey arrows indicate the directions of the Sun, Earth, and Dinkinesh, respectively. The red arrow indicates motion of the spacecraft- to the right on the graphic.

NASA’s Lucy Spacecraft Hours Away from 1st Asteroid Encounter

We are only a few hours away from the NASA Lucy spacecraft’s first close up look at the small inner-main belt asteroid, Dinkinesh. Dinkinesh is 10 to 100 times smaller than the Jupiter Trojan asteroids that are the mission’s main targets.

artist conception of Lucy spacecraft flying by asteroid Dinkinesh

NASA’s Lucy Spacecraft Ready for 1st Asteroid Encounter

NASA’s Lucy spacecraft is on track for its first asteroid encounter on Nov. 1. Lucy’s optical navigation team has confirmed that the latest trajectory correction maneuver on Sept 29 accurately set the spacecraft on course for its flyby of the small main belt asteroid Dinkinesh.

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