Gaia satellite operations come to an end
The European Space Agency (ESA) has shut down the Gaia space satellite after more than a decade of scientific mission to collect data that is now being used to uncover the secrets of our galaxy. On 27 March 2025, Gaia’s control team at ESA’s European Space Operations Centre switched off the spacecraft’s subsystems and sent it into a ‘retirement orbit’ around the Sun. Although spacecraft operations have now ended, the scientific exploitation of Gaia’s data has just begun.
Since its beginnings, the Gaia mission, ESA’s most ambitious project to study the history and structure of the Milky Way, has involved a team of astronomers and engineers from the Department of Quantum Physics and Astrophysics of the Institute of Cosmos Sciences of the University of Barcelona (ICCUB) and the Institute of Space Studies of Catalonia (IEEC).
The European Space Agency (ESA) has shut down the Gaia space satellite after more than a decade of scientific mission to collect data that is now being used to uncover the secrets of our galaxy. On 27 March 2025, Gaia’s control team at ESA’s European Space Operations Centre switched off the spacecraft’s subsystems and sent it into a ‘retirement orbit’ around the Sun. Although spacecraft operations have now ended, the scientific exploitation of Gaia’s data has just begun.
Since its beginnings, the Gaia mission, ESA’s most ambitious project to study the history and structure of the Milky Way, has involved a team of astronomers and engineers from the Department of Quantum Physics and Astrophysics of the Institute of Cosmos Sciences of the University of Barcelona (ICCUB) and the Institute of Space Studies of Catalonia (IEEC).
Gaia’s stellar contributions
Launched in 2013, the Gaia satellite has transformed our understanding of the cosmos by mapping the positions, distances, motions and properties of nearly two billion stars and other celestial objects. ESA’s star mission has provided the largest and most accurate multidimensional map of our galaxy ever created, revealing its structure and evolution in unprecedented detail.
The mission discovered past galactic mergers, identified new star clusters, contributed to the discovery of exoplanets and black holes, mapped millions of quasars and galaxies, and tracked hundreds of thousands of asteroids and comets. It also created the best visualisation of what our galaxy might look like to an outside observer.
“Gaia’s extensive data releases are a unique treasure trove for astrophysical research and influence almost all disciplines of astronomy”, says Johannes Sahlmann, Gaia project scientist. “Data release 4, planned for 2026, and the final Gaia legacy catalogues, planned for release no earlier than the end of 2023, will continue shaping our scientific understanding of the cosmos for decades to come”.
Xavier Luri, professor at the Department of Quantum Physics and Astrophysics, director of the ICUCB and member of the IEEC, stresses that “the Gaia team at the UB has worked on the mission since its beginnings, around 1997”. “Since then, it has been involved in all phases, from the definition of the scientific case and industrial design to data processing and scientific exploitation”, he continues. “Now, although Gaia completes the observations, we still need several years of work to fully process the total data collected during this period and to publish two additional data deliveries (DR4 and DR5)”.
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Since its beginning, the Gaia mission, has involved a team of astronomers and engineers from the Institute of Cosmos Sciences (ICCUB) of the University of Barcelona and the Institute of Space Studies of Catalonia (IEEC).
On 27 March 2025, Gaia’s control team at ESA’s European Space Operations Centre switched off the spacecraft’s subsystems.
