Gaia Mission

The Gaia spacecraft, a successor to the Hipparcos mission, is an unmanned mission by the European Space Agency (ESA), designed to create the most accurate and complete map of the Milky Way. Thanks to Gaia, astronomers can study the structure, history, and evolution of our Galaxy with unprecedented precision. The data and derived results are publicly released, allowing both professionals and amateur astronomers to benefit from this vast repository of knowledge.

Launched in 2013, Gaia operated continuously for 11 years. It orbited approximately 1.5 million km from Earth, conducting sky observations with two telescopes. Data collection concluded in early 2025, leaving behind an impressive archive covering around 2 billion celestial objects, which is only about 1% of all objects in the Milky Way. The spacecraft repeatedly monitored positions, distances, proper motions, brightness, chemical composition, and variability of stars and other celestial bodies. Gaia performed astrometric measurements to analyze positions, distances, and motions, as well as photometric and spectroscopic observations, providing information on stellar brightness, temperatures, and evolutionary stages.

Based on the collected data, astronomers have created the most precise three-dimensional map of our Galaxy. Gaia’s results are crucial for galactic archaeology, the study of the Milky Way’s history. They have improved our understanding of the structure of spiral arms, the rotation of the central Galactic bar, and the distribution of interstellar dust near the Sun.

During its mission, Gaia also discovered thousands of asteroids, distant galaxies, and quasars—the extremely bright cores of galaxies. One of the most spectacular findings was the identification of a new type of black hole, including one with a mass 33 times that of the Sun, located just 2,000 light-years from Earth.Scientists from the Astronomical Observatory of the University of Warsaw have been actively involved in the Gaia project for many years. Although the spacecraft no longer collects data, analysis continues. The fourth Gaia catalog (Gaia DR4) is being prepared for release in 2026. It will include approximately 500 TB of data, covering new exoplanets, binary stars, and previously unknown black holes.