Moon Discovered Around Asteroid Polymele by NASA's Lucy Team - SciTechDaily

Lucy will explore the Jupiter Trojan asteroids – thought to be “fossils of planet formation.” Credit: NASA’s Goddard Space Flight Center.

Even before its launch in October 2021, NASA’s Lucy mission was already on course to break records by visiting more asteroids than any previous mission.

Lucy’s science team discovered on March 27 that the smallest of the mission’s Trojan asteroid targets, Polymele, has a satellite of its own.

The Lucy team planned to measure the location, size, and shape of Polymele with unprecedented precision while it was outlined by the star behind it.

A graphic showing the observed separation of asteroid Polymele from its discovered satellite.

Credit: NASA’s Goddard Space Flight Center.

A graphic showing the observed separation of asteroid Polymele from its discovered satellite.

Credit: NASA’s Goddard Space Flight Center.

As the satellite is too close to Polymele to be clearly seen by Earth-based or Earth-orbiting telescopes – without the help of a fortuitously positioned star – that determination will have to wait until Lucy approaches the asteroid in 2027, unless the team gets lucky with future occultation attempts before then.

Credit: NASA’s Goddard Space Flight Center.

The Lucy team originally planned to visit one main belt asteroid and six Trojan asteroids, a previously unexplored population of asteroids that lead and follow Jupiter in its orbit around the Sun.

In January of 2021, the team used the Hubble Space Telescope to discover that one of the Trojan asteroids, Eurybates, has a small satellite.

Shortly after the Lucy team discovered the satellite, both it and Eurybates moved behind the Sun, preventing the team from observing it further.

NASA’s Goddard Space Flight Center in Greenbelt, Maryland, provides overall mission management, systems engineering, and safety and mission assurance.

NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Discovery Program for the agency’s Science Mission Directorate in Washington