Flyby of Asteroid Donaldjohanson
During its close approach last year, NASA’s Lucy spacecraft conducted a detailed survey of the asteroid Donaldjohanson. Measurements indicate that the body is far from spherical, displaying a distinctive peanut‑shaped outline with pronounced lobes.
Complex Rotational Motion
Analysis shows that the asteroid not only has an irregular shape but also rotates in a tumbling manner, known as wobbling, suggesting that it has experienced significant external torques in its past.
Formation History
Approximately 155 million years ago a violent collision in the asteroid belt generated a cloud of debris. The fragments later coalesced to form Donaldjohanson, with the impact dynamics imprinting its current shape.
Activity Over a Short Timespan
Despite its modest size, the asteroid has undergone several episodes of activity, including possible impacts by smaller meteoroids and thermal stresses that may have contributed to its wobble.
Implications for Planetary Science
The findings from Lucy provide new insights into how small bodies in the Solar System are assembled and evolve. Understanding these processes is essential for assessing the threat posed by near‑Earth objects.