When the Hubble Space Telescope gazes out into the distance, it doesn't just see the far-off subjects it's focusing on. It also sees objects that slip into its field of vision, like asteroids. A new look at a 2005 Hubble image of the crustacean-shaped Crab Nebula showed an arcing asteroid trail photobombing the scenery.
The nifty enhanced image came about through the Hubble Asteroid Hunter citizen-scientist project through the European Space Agency. Volunteers looked through the Hubble image archive in search of asteroid trails.
"Knowing the date and time when the Hubble images were taken, they can use the trails marked in the pictures to infer asteroids' positions and velocities," ESA said in a release on Monday. "This means they can determine the orbits and future trajectories of known and previously unknown asteroids with greater precision than before."
Volunteer asteroid hunter Melina Thévenot spotted the space rock in the Crab Nebula image and then processed the image to highlight the asteroid's path.
The Hubble Space Telescope is a joint project of ESA and NASA. Mining old images for asteroid data will be useful for scientists who are studying near-Earth objects (NEOs) that could potentially threaten our planet.
The Crab Nebula is a regular for Hubble. It was the focus of the telescope's anniversary image for 2019. ESA plans to post a new set of images to the Hubble project soon, so there will be an opportunity to join the 1,900 volunteers and become an asteroid hunter, which is just about the coolest job description ever.