NASA Lucy Spacecraft Snaps Asteroid Donaldjohanson from 600 Miles Away

NASA’s Lucy spacecraft captured close-up images of an asteroid formed about 150 million years ago.

NASA reports that the Lucy spacecraft flew just 600 miles (960 kilometers) from the asteroid Donaldjohanson on April 20, 2025. The asteroid Donaldjohanson fascinates scientists because it has previously been observed showing significant brightness variations over 10 days. This led Lucy team members to theorize that the asteroid was an elongated contact binary, an object formed when a pair of smaller bodies collide. These beliefs were confirmed when Lucy returned its first images of the asteroid to Earth.

However, the close encounter unveiled something surprising about the 150-million-year-old asteroid careening through space. The asteroid is shaped like two nested ice cream cones.

“Asteroid Donaldjohanson has strikingly complicated geology,” explains Hal Levison, principal investigator for Lucy at Southwest Research Institute, Boulder, Colorado.

“As we study the complex structures in detail, they will reveal important information about the building blocks and collisional processes that formed the planets in our Solar System.”

Early analysis of the photos Lucy captured with its L’LORRI imager shows that the asteroid is larger than initially estimated — about five miles (eight kilometers) long and two miles (3.5 kilometers) wide at its widest point. The asteroid is so large, and Lucy was so close that the first images returned to Earth can’t capture the entire object in one frame. Additional photos will take about a week to arrive to Earth and hopefully offer a more complete picture of asteroid Donaldjohanson.

This is not the first time Lucy has made a surprising discovery during a close flyby of an asteroid. In November 2023, when Lucy returned the photos from its first-ever asteroid encounter with Dinkinesh, scientists were shocked to find that L’LORRI captured images of Dinkinesh and a smaller satellite object. (https://petapixel.com/2023/11/16/nasa-spacecrafts-first-photo-of-an-asteroid-reveals-a-surprise/)

And like Dinkinesh, Donaldjohanson is not one of Lucy’s primary scientific targets. However, the asteroid is no less fascinating.

“These early images of Donaldjohanson are again showing the tremendous capabilities of the Lucy spacecraft as an engine of discovery,” explains Tom Statler, program scientist for the Lucy mission at NASA Headquarters in Washington. “The potential to really open a new window into the history of our solar system when Lucy gets to the Trojan asteroids is immense.”

NASA’s Lucy spacecraft will spend most of this year traveling through the main asteroid belt before encountering its first primary mission target, the Jupiter Trojan asteroid Eurybates, in August 2027. The images of that encounter are sure to be astounding.

Image credits: NASA/Goddard/SwRI/Johns Hopkins APL/NOIRLab