Possible Moons Have Been Detected Orbiting Hundreds of Asteroids.

Observations conducted by the Gaia Space Telescope have the potential to enhance the known catalog of asteroids that possess moons significantly.

The European Space Agency’s (ESA) Gaia space telescope has made a significant discovery by identifying potential moons around over 350 previously unknown asteroids with companions. These findings expand our understanding of binary asteroids — systems composed of a parent asteroid and one or more orbiting moons.

The telescope has previously explored asteroids known to possess moons and confirmed their presence through highly precise astrometric data. However, the discovery demonstrates its capability to conduct searches for new binary system candidates, even in the absence of prior knowledge about the existence of moons.

Luana Liberato, a researcher at the Observatoire de la Côte d’Azur in France and the lead author of a recently published study, observed that the majority of binary asteroids are challenging to detect due to their small size and considerable distance. While it is estimated that approximately one-sixth of asteroids possess at least one moon, only 500 binary systems have been identified among the more than 1 million known asteroids. The recent discovery introduces 352 new candidates to the list of binary asteroids, nearly doubling the number currently recognized.

Asteroids play a crucial role in enhancing our understanding of the formation and evolution of the Solar System, and binary systems provide additional insights into the dynamics of formation and interactions between these bodies. Gaia has contributed significantly to this field through the precise determination of the positions and motions of over 150,000 asteroids. This advancement has enabled scientists to identify wobbles caused by the presence of moons and to refine measurements of asteroid orbits with accuracy improved by up to 20 times.