Gaia space telescope finds potential moons around 350 asteroids

The European Space Agency’s Gaia space telescope has made a major breakthrough in asteroid research. It has discovered potential moons orbiting more than 350 previously thought solitary asteroids. The finding, detailed in Gaia’s Data Release 3 (DR3), suggests that the number of binary asteroid systems in our Solar System could nearly double.

Gaia has now demonstrated that it can perform “blind searches” for new asteroid-moon pairs. The telescope’s observations indicate that many asteroids have hidden moons that had previously gone undetected. This discovery underscores Gaia’s role in expanding our understanding of these small bodies.

According to Luana Liberato, the principal investigator at the Côte d’Azur Observatory, binary asteroids are difficult to identify because of their small size and great distance from Earth. Despite expectations that about a sixth of asteroids could have companions, only 500 of the billion known asteroids have previously been identified as binary systems. The new data from Gaia’s DR3 release shows that there are many more such systems waiting to be discovered.

Asteroids, the remnants of the early solar system, offer valuable insights into its formation and evolution. By studying these objects, scientists hope to better understand the conditions of the early solar system and the possible role of asteroids in delivering essential organic materials to Earth. The discovery of binary asteroids adds another layer to this research by revealing how collisions and interactions between these bodies may have shaped our planetary system.

Gaia’s precise measurements have revealed subtle “wobbles” in asteroid orbits, indicating the presence of smaller moon-like companions. This advance not only expands our knowledge of asteroids, but also lays the foundation for future discoveries. The upcoming Data Release 4 in 2026 is expected to provide even more insight into asteroid-moon systems, further enhancing our understanding of these ancient space objects.