The European Space Agency (ESA) officially shut down its Gaia spacecraft mission, a landmark project that mapped nearly 2 billion stars and reshaped our understanding of the Milky Way.
On Thursday, mission controllers at ESA’s operations center in Darmstadt shut down the spacecraft’s systems and guided it into a stable orbit around the sun.
The final maneuver moved Gaia from its previous location near the Sun-Earth Lagrange Point 2, where it had operated for over a decade.
Though Gaia is now silent, its scientific legacy continues. Data collected during the mission will support research for decades, helping scientists explore the structure of our galaxy, trace its history, and study stars, planets, and more.
Transforming astronomy since 2013
Launched in 2013, Gaia was built to chart the positions, movements, and properties of stars with unmatched precision.
It created the most detailed map of the galaxy ever produced, revealing ancient mergers between galaxies, and new clusters of stars and contributing to the discovery of black holes and planets beyond our solar system.
The spacecraft also tracked hundreds of thousands of asteroids and offered a striking visual of how the Milky Way might appear from the outside.
“Gaia’s extensive data releases are a unique treasure trove for astrophysical research, and influence almost all disciplines in astronomy,” said Gaia project scientist Johannes Sahlmann.
“Data release 4, planned for 2026, and the final Gaia legacy catalogs, planned for release no earlier than the end of 2030, will continue shaping our scientific understanding of the cosmos for decades to come.”
A mission that outlasted its design
Originally designed for a five-year mission, Gaia operated for over 10 years. As its fuel supply ran low, ESA teams prepared a careful shutdown plan to avoid interference with future missions in the L2 region. Engineers performed “passivation” procedures to safely disable the spacecraft.
That process was not simple. Gaia was built to survive extreme conditions, from solar storms to micrometeorites, and had multiple backup systems designed to restore operations after failures.
Engineers had to manually disable these protections to ensure the spacecraft wouldn’t restart if its solar panels caught sunlight again.
A deliberate and emotional farewell
The shutdown concluded with a critical step: corrupting Gaia’s onboard software to prevent future reactivation. Instruments, subsystems, and the communication system were turned off individually.
The disappearance of @ESAGaia!
On 4 March, astronomer Zhuo-Xiao Wang captured this view of the sudden disappearance of ESA’s Gaia spacecraft.
Credit: Zhuo-Xiao Wang, CC BY-SA 3.0 IGO
Observations performed on 4 March 2025 using an 11-inch telescope from Beijing, China (MPC site… pic.twitter.com/mHMNNQ2eH3— ESA Operations (@esaoperations) March 18, 2025
“Today, I was in charge of corrupting Gaia’s processor modules to make sure that the onboard software will never restart again once we have switched off the spacecraft,” said spacecraft operations engineer Julia Fortuno.
“I have mixed feelings between the excitement for these important end-of-life operations and the sadness of saying goodbye to a spacecraft I have worked on for more than five years. I am very happy to have been part of this incredible mission.”
Helping shape future missions
In its final weeks, the Gaia team also ran technical tests, including checks on its micro-propulsion system to study how it aged in space. The results may help improve systems in future ESA missions like LISA, a planned space observatory.
Even in retirement, Gaia’s work isn’t done. Its data continues to guide new missions. ESA’s Euclid spacecraft uses Gaia’s star maps for navigation, and the upcoming Plato mission will study planets around stars identified by Gaia.
Final moments with the team
The farewell was also personal. As a tribute, engineers wrote the names of 1,500 team members into Gaia’s memory, replacing parts of unused backup software. Personal goodbye messages were added too, leaving a lasting imprint on the people behind the mission.
🚨NEWS – ESA CONFIRMS END OF GAIA MISSION.
In a carefully choreographed final sequence, ESA first Gaia’s thrusters one last time, sending the spacecraft off to a retirement orbit…
“We will never forget Gaia, and Gaia will never forget us,” – Uwe Lammers, Gaia Mission… pic.twitter.com/kswnICMe8H
— The Launch Pad (@TLPN_Official) March 27, 2025
“We will never forget Gaia, and Gaia will never forget us,” said mission manager Uwe Lammers.
With the final signal, ESA shuts down the Gaia spacecraft, marking the end of operations, but its journey through space—and its influence on science—will continue for generations.