|Names||Discovery Mission 13|
|Mission type||Multiple-flyby of asteroids|
|Operator||NASA Goddard · SwRI|
|Mission duration||12 years (planned)|
3 days, 12 hours and 45 minutes (in progress)
|Launch mass||1,500 kg (3,300 lb)|
|Dimensions||13 m (43 ft) in long |
Each solar panel: 7.3 m (24 ft) in diameter
|Power||504 watts (furthest encounter)|
|Start of mission|
|Launch date||16 October 2021, 09:34:00 UTC|
|Rocket||Atlas V 401 (AV-096)|
|Launch site||Cape Canaveral, SLC-41|
|Contractor||United Launch Alliance|
|High-resolution visible imager (L'LORRI)|
Optical and near-infrared imaging spectrometer (L'Ralph)
Thermal infrared spectrometer (L'TES)
Lucy mission patch
Lucy is a NASA space probe on a twelve-year journey to eight different asteroids, visiting a main belt asteroid as well as seven Jupiter trojans, asteroids which share Jupiter's orbit around the Sun, orbiting either ahead of or behind the planet. All target encounters will be fly-by encounters. The Lucy spacecraft is the centerpiece of a US$981 million mission.
The mission is named after the Lucy hominin fossils, because study of the trojans could reveal the "fossils of planet formation": materials that clumped together in the early history of the Solar System to form planets and other bodies. The hominid was named after the 1967 Beatles song "Lucy in the Sky with Diamonds". The spacecraft carries a disc made of lab-grown diamonds for its L'TES instrument.
Lucy was launched from Cape Canaveral SLC-41 on 16 October 2021 on the 401 variant of a United Launch Alliance Atlas V launch vehicle, after which it will gain two gravity assists from Earth; one in 2022, and one in 2024. In 2025, it will fly by the inner main-belt asteroid 52246 Donaldjohanson, which was named after the discoverer of the Lucy hominin fossil. In 2027, it will arrive at the L4 Trojan cloud (the Greek camp of asteroids that orbits about 60° ahead of Jupiter), where it will fly by four Trojans, 3548 Eurybates (with its satellite), 15094 Polymele, 11351 Leucus, and 21900 Orus. After these flybys, Lucy will return to Earth in 2031 for another gravity assist toward the L5 Trojan cloud (the Trojan camp which trails about 60° behind Jupiter), where it will visit the binary Trojan 617 Patroclus with its satellite Menoetius in 2033. The mission may end with the Patroclus–Menoetius flyby, but at that point Lucy will be in a stable, 6-year orbit between the L4 and L5 clouds, and a mission extension will be possible.
Three instruments comprise the payload: a high-resolution visible imager, an optical and near-infrared imaging spectrometer, and a thermal infrared spectrometer. Harold F. Levison of the Southwest Research Institute in Boulder, Colorado is the principal investigator, with Cathy Olkin of Southwest Research Institute as the mission's deputy principal investigator. NASA's Goddard Space Flight Center will manage the project.
Exploration of Jupiter Trojans is one of the high-priority goals outlined in the Planetary Science Decadal Survey. Jupiter Trojans have been observed by ground-based telescopes and the Wide-field Infrared Survey Explorer to be "dark with... surfaces that reflect little sunlight". Jupiter is 5.2 AU (780×106 km; 480×106 mi) from the Sun, or about five times the Earth-Sun distance. The Jupiter Trojans are at a similar distance but can be somewhat farther or closer to the Sun depending on where they are in their orbits. There may be as many Trojans as there are asteroids in the asteroid belt.
NASA selected Lucy through the Discovery Program AO released on 5 November 2014. Lucy was submitted as part of a call for proposals for the next mission(s) for Discovery Program that closed in February 2015. Proposals had to be ready to launch by the end of 2021. Twenty-eight proposals were received in all.
On 30 September 2015, Lucy was selected as one of five finalist missions, each of which received US$3 million to produce more in-depth concept design studies and analyses. Its fellow finalists were DAVINCI, NEOCam, Psyche and VERITAS. On 4 January 2017, Lucy and Psyche were selected for development and launch.
On 31 January 2019, NASA announced that Lucy would launch in October 2021 on an Atlas V 401 launch vehicle from Cape Canaveral, Florida. The total cost for the launch is estimated to be US$148.3 million. On 11 February 2019, SpaceX protested the contract award, claiming that it could launch Lucy into the same orbit at a "significantly cheaper cost". On 4 April 2019, SpaceX withdrew the protest.
On 28 August 2020, NASA announced that Lucy had passed its Key Decision Point-D (KDP-D) with a "green light" to assemble and test the spacecraft and its instruments. The spacecraft instruments arrived beginning with L'LORRI on 26 October 2020. On 30 July 2021, the spacecraft was transported on a C-17 transport aircraft to Florida for launch preparations, and Lucy was encapsulated into the rocket fairing on 30 September 2021.
|16 October 2022||Earth||Terrestrial planets||12 742 km||300 km||Terrestrial planet||Gravity assist|
|13 December 2024||Earth||Terrestrial planets||12 742 km||350 km||Terrestrial planet||Gravity assist|
|20 April 2025||52246 Donaldjohanson||Inner main belt||4 km||922 km||C-type asteroid.||Member of ~130 Myr old Erigone collisional family.|
|12 August 2027||3548 Eurybates||Greek camp at L4||Eurybates: 64 km
(Queta satellite: 1 km)
|1000 km||Binary C-type asteroid||Largest member of the only confirmed disruptive collisional family in the Trojans.|
|15 September 2027||15094 Polymele||Greek camp at L4||21 km||415 km||P-type asteroid||May be a collisional fragment of a larger P-type asteroid. Its red color suggests surface is rich in organic tholin compounds.|
|18 April 2028||11351 Leucus||Greek camp at L4||34 km||1000 km||D-type asteroid||slow rotator taking 466 hours per rotation.|
|11 November 2028||21900 Orus||Greek camp at L4||51 km||1000 km||D-type or C-type asteroid according to the Lucy mission team and by Pan-STARRS photometric survey, respectively.||Possible binary.|
|26 December 2030||Earth||Terrestrial planets||12 742 km||660 km||Terrestrial planet||Gravity assist. First spacecraft to go as far as Jupiter's orbit and return to the vicinity of the Earth.|
|2 March 2033||617 Patroclus-Menoetius||Trojan camp at L5||Patroclus: 113 km
Menoetius: 104 km
|1000 km||Binary P-type asteroids.||The pair orbit at a separation of 680 km|
|Wikimedia Commons has media related to Lucy (spacecraft).|