The astrometric satellite Gaia has now completed the sky-scanning phase of its mission and has reached the end of its science observations. Gaia will soon be moved to its ‘retirement’ orbit.
Launched on 19 December 2013, the European Space Agency’s astrometric satellite Gaia has now completed the sky-scanning phase of its mission and has reached the end of its science observations. Its three trillion observations of two billion stars and other objects revolutionized our view of the Milky Way and our cosmic neighborhood.
A large pan-European team of expert scientists and software developers known as DPAC (Data Processing and Analysis Consortium) was - and still is - responsible for the processing of Gaia's data with the final objective of producing the Gaia data products which are exploited by scientists worldwide and made the mission so incredibly successful.
In Heidelberg, a team of scientists and software engineers at the Astronomisches Rechen-Institut (ARI) of the Center for Astronomy at the University of Heidelberg (ZAH) is part of DPAC. In fact, it's the largest department of the consortium and responsible for the entire processing chain from the satellite's raw data to the creation of the mission's main astrometric product. Dr. Michael Biermann, head of the Heidelberg DPAC group, comments on the end of science observations: “Since the satellite was launched more than ten years ago, Gaia has somehow become our baby. We have always had to look after its well-being, take care of it on a daily basis when something was wrong and find ways to deal with Gaia's small and large teething problems. Of course it hurts when contact is then forced to break off at some point.”
In 2023, the Gaia Collaboration received the Berkeley Prize for meritorious work in astronomy. This also was a credit to the Gaia team at ARI. "We were really proud to receive this award in recognition of the achievements of the entire Gaia team. This success is also the result of our work here in Heidelberg, which did not just begin after the launch of Gaia, but decades earlier." Dr. Biermann resumes.
Dr. Biermann's team had developed, amongst other components, a highly complex software that monitored the correct performance of all systems of Gaia and the quality of the raw scientific data on a daily basis. The ARI team of experts also leads the pan- European astrometry department, which extracts from the trillions of measurements the data scientists used already successful as never before to expand our knowledge about the origin and structure of our home galaxy. ARI also hosts one of six Gaia data centers, and coordinated the "Gaia Ground Based Optical Tracking", whose task was to accurately monitor the satellite's position in the sky and measure its motion as one of the manyfold prerequisites for the ultra-precise astrometry.
Gaia’s fuel tank is now approaching empty. But this is far from the end of the mission. Technology tests are scheduled before Gaia is eventually moved to its ‘retirement’ orbit, and two massive data releases are tabled for around 2026 and the end of this decade, the Gaia Data Release #4 and #5, respectively.
Even if the satellite no longer provides data, it can be assumed that there will still be a large number of publications in the coming years based on the observations carried out and the finished data products provided by the ARI team. Gaia is already one of the most successful research missions ever, yet with 13,000 scientific publications in around ten years.
"Farewell, Gaia, and all the best for your eternal orbit through the solar system."
ADDITIONAL INFORMATION
ESA press release
https://www.esa.int/Science_Exploration/Space_Science/Gaia/Last_starlight_for_groun d-breaking_Gaia
Gaia Data Releases 1-3
www.cosmos.esa.int/web/gaia/data
Information provided by the Gaia Group at the Astronomisches Rechen-Institut (ARI)
zah.uni-heidelberg.de/gaia
Gaia based publications
https://ui.adsabs.harvard.edu/public-libraries/Vl-O8dzhSieTyQOaV-wAfg
Astro&Co: Lettes Sternlicht für Gaia (in German)
https://astrodon.social/@hausderastronomie/113854528734671901
LOCAL CONTACTS
Contact for the Media
Dr. Guido Thimm
Center for Astronomy at Heidelberg University (ZAH)
thimm@uni-heidelberg.de
Scientific contact
Dr. Michael Biermann
Center for Astronomy at Heidelberg University (ZAH)
Astronomisches Rechen-Institut (ARI)
biermann@ari.uni-heidelberg.de
Gaia outreach contact
Apl. Prof. Dr. Stefan Jordan
Center for Astronomy at Heidelberg University (ZAH)
Astronomisches Rechen-Institut (ARI)
jordan@ari.uni-heidelberg.de
