Charting a three-dimensional map of our Galaxy and contributing to a database of potentially hazardous near-Earth objects

ESA’s GAIA satellite has completed its ambitious mission to map the Milky Way in 3D. As it scanned the sky surveying stars in the Milky Way galaxy, Gaia was also able to detected a wealth of asteroids and comets, significantly contributing to the search for potentially hazardous near-Earth objects (NEOs). With its exceptional sensitivity to faint, moving objects, GAIA has helped identify NEOs that could pose a risk to Earth. It has also made exciting discoveries, including spotting potential moons around more than 350 asteroids that were previously thought to be moonless.

In addition to its work within the Solar System, GAIA’s precise measurements have provided new insights into the history of our galaxy. By studying the motions and distances of stars, it uncovered traces of ancient galaxy mergers and shed light on the ongoing collision with the Sagittarius dwarf galaxy, helping us understand the past and future of the Milky Way.

Beyond the Milky Way, GAIA mapped the orbits of over 150,000 asteroids and created the largest 3D map of 1.3 million quasars — some of which are as distant as when the Universe was just 1.5 billion years old. 

Throughout the mission, GAIA detected hundreds of thousands of minor planets, including many new discoveries. These included NEOs, asteroids in the main belt between Mars and Jupiter, and objects in the outer Solar System’s Kuiper Belt. GAIA’s data continues to play a key role in monitoring asteroid impact risks, helping scientists assess potential threats and explore ways to mitigate or even divert dangerous objects.