Lucy

First to the Trojans

This October, a spacecraft will launch toward a type of asteroids that has never been visited by a spacecraft before, Jupiter Trojans. These asteroids are relics from the early solar system. The Lucy spacecraft may help us understand how the solar system formed, just as the "Lucy" skeleton helped us understand how humans evolved.

The Destinations

The Lucy spacecraft will visit a kind of asteroid called Jupiter Trojans. Jupiter Trojans orbit around the sun in the same orbit as Jupiter. They orbit spots known as Lagrange points, which are places of stability where gravity from the Sun and Jupiter are balanced. There are two clusters of Trojans one is ahead of Jupiter, and one is behind. The leading group of Trojans are called Greeks and the trailing group are called Trojans. Little is known about either group of asteroids.

Lucy will visit asteroids in both groups in addition to an asteroid in the asteroid belt.

Photo Credit: NASA/JPL-Caltech

The Spacecraft

The Lucy spacecraft consists of a spacecraft bus constructed by Lockheed Martin, a large communications antenna, two large solar arrays, and a moving platform that contains scientific instruments. The fan shaped solar arrays were built by Northrop Grumman and are 6 meters in diameter. The spacecraft will maneuver itself using hydrazine thrusters. On the front of the spacecraft is the IPP (Instrument Pointing Platform). 4 scientific instruments will be attached to the IPP. To keep costs low, many of these scientific instruments are based on instruments currently flying on New Horizons and OSIRIS-REx.

Photo Credit: Southwest Research Institute

Mission Events

Lucy launched on October 16th, 2021, on an Atlas V rocket. The spacecraft will fly past Earth in 2022, then again in 2024 to gain enough speed to head out into the outer solar system. On it's way there it will flyby a main-belt asteroid called Donaldjohansen. Between 2028 and 2029, Lucy will fly by 4 asteroids in the Greek camp (one of which is a binary asteroid.) It will then briefly return to the inner solar system and perform one final Earth flyby before heading to the Trojan camp. Lucy will perform it's last flyby in 2033.

After that, it's primary mission will be complete, and NASA may decide to let Lucy continue studying Jupiter Trojans.

Oct. 16th, 2021	Launch of Lucy
Oct. 15th, 2022	First Earth flyby
Dec. 12th, 2024	Second Earth flyby
Apr. 20th, 2025	Lucy visits main-belt asteroid Donaldjohnasen
Aug. 12th, 2027	Lucy visits Eurybates ans Queta
Sep. 15th, 2027	Lucy visits Polymele
Apr. 18th, 2028	Lucy visits Leucus
Nov 11th, 2028	Lucy visits Orus
Dec 25th, 2030	Third Earth flyby
Mar 2nd, 2033	Lucy visits Patroclus and Menoetius

This video shows the trajectory that the Lucy spacecraft will take. Credit: NASA/SwRI

Lucy Mission Trailer

To learn more visit the Lucy website at: lucy.swri.edu

Or read this poster has some useful information about the mission:

lucy.swri.edu/img/graphics/LucyPoster_Mission_of_Discovery.pdf

Other interesting web pages about the Lucy mission: