Image of the Week

Farewell, Gaia! A short movie on the Gaia spacecraft passivation

Video 1. The above video was created in the framework of the ERC-Consolidator Grant (2021-2026) "Visual Trust: Reliability, accountability and forgery in scientific, religious and social images" by the University of Barcelona. It gives highlights of the day the Gaia spacecraft was passivated. Credit: Visual Trust, University of Barcelona, ESA/Gaia/DPAC. Acknowledgements: Alkim Erol. More information here. Full credits below.

The European Space Agency (ESA) has powered down its Gaia spacecraft after more than a decade spent gathering data. Data that are now being used to unravel the secrets of our home galaxy. On 27 March 2025, Gaia’s control team at ESA’s European Space Operations Centre carefully switched off the spacecraft’s subsystems and sent it into a ‘retirement orbit’ around the Sun. Though the spacecraft’s operations are now over, the scientific exploitation of Gaia’s data has just begun.

The spacecraft has been an enormous success, but the people behind the mission make it all happen. From the team proposing the mission, through the people designing and building the spacecraft to the people who keep the spacecraft healthy and operational. Decades of dedication to a wonderful mission. While the spacecraft is now retired, the mission continues in its post-operational phase.

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Video 2. The moment the signal of the Gaia spacecraft transponder went down ... an emotional moment for many people from the Gaia mission teams... so long, Gaia! Credits: ESA/Gaia.

A team of over 450 scientists and engineers work on the Gaia data processing, a massive job to transform the raw telemetry from the spacecraft into scientific parameters published in the Gaia catalogues. For each new data release, more data is processed, calibrations are improved and more data types can be extracted thanks to the longer observation timeline. 

Virtual group picture of the Gaia Data Processing and Analysis Consortium as taken right before the Gaia Data Release 3 in May 2022 during one of the Gaia DPAC seminars. Credits: ESA/Gaia/DPAC

Two large data releases are still planned: Gaia Data Release 4 (Gaia DR4) in December 2026 and the final legacy catalogue is expected not before the end of 2030. An update of the Gaia DR4 contents will be provided later this week. Gaia Data Release 4 will in fact be the first true release for the Gaia mission, where all data types are released for the full nominal mission period. The first data releases already transformed astronomy completely, and more is yet to come!

More information on the passivation of the Gaia spacecraft can be found from the following pages:

• Spacecraft passivation page
• News release "Farewell, Gaia! Spacecraft operations come to an end"
• Story "A milestone for the Gaia mission: retirement orbit and passivation"
• ESA's Gaia spacecraft leaves for retirement orbit​​​​​​

Credits and acknowledgements for the video shown in Video 1:

The above video was created in the framework of the ERC-Consolidator Grant (2021-2026) "Visual Trust: Reliability, accountability and forgery in scientific, religious and social images" by the University of Barcelona.

Direction, Research and Camera by Alkim Erol. Editing by Òscar Hidalgo. Research Coordinator: Roger Canals. Special thanks to Gaia Team, Gaia Collaboration, all the Gaia Space Mission Colleagues at ESA and all the participants of the Gaia Passivation Event at ESOC. Archive Videos and Images: The insert images and videos are derived from European Space Agency Archive and the copyright of these images belongs to ESA: https://www.esa.int/esatv/Videos_for_Professionals.

Also recognised are the image and video contributions by ESA/Gaia/DPAC, Gaia Sky, Zhuoxiao Wang, Stefan Payne-Wardenaar as shared under the CC BY-SA 3.0 IGO license. Gaia Goes on' video is credited to ESOC Musicians Club and ESOC film Club. All images are used with permission. Music and Sound: "Space Ambience" freesound_community / Jupiter" Elysium Sound / "Science and Research" DIMMYSA / "Motivational Inspirational 80s background" ABSounds / Freesound  / Pixabay / Free Music Archive ​​/ SoundEffectsFactory. 

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Figure 2. The focal plane was shut down one CCD at a time. Gaia sends us a final message: Bye! Credits: Jos de Bruijne.
 

Credits: ​​​​​​​ESA/Gaia/DPAC, Visual Trust, University of Barcelona

Prepared by T. Roegiers

[Published: 16/12/2025]