NASA’s Lucy spacecraft is nearing its highly anticipated encounter with small main belt asteroid Donaldjohanson. The asteroid’s brightness appears as a series of points in front of a static background, with periodic brightening and dimming on a 10-day cycle. This suggests the asteroid is a slowly rotating elongated object.
To ensure accuracy, NASA’s navigation team made a small trajectory correction maneuver on April 13, adjusting the spacecraft’s velocity by 0.15 mph to reach its planned aimpoint. The team will maintain communication with the spacecraft until it switches to autonomous tracking, approximately 30 minutes before closest approach. After that, the spacecraft will use its terminal tracking system to rotate and keep the asteroid in view, momentarily pausing Earth-based contact.
Following the encounter, the spacecraft will reestablish contact in hours, but it may take up to a week to downlink data collected during the event.
Source: https://science.nasa.gov/blogs/lucy/2025/04/18/nasas-lucy-days-away-from-asteroid-encounter