Gaia’s Grand Finale: Celebrating a Decade of Discovery with Hungarian Astronomers

20.01.2025

During its extensive mission spanning more than ten years, Gaia has continuously assessed the positions of stars as well as variations in their brightness. These measurements have facilitated the determination of distances, movements, chemical compositions, and various other attributes of nearly two billion cosmic sources of light, as reported on konkoly.hu. This work has allowed Gaia to achieve its principal objective: constructing the largest and most accurate map of the Milky Way, providing us with a perspective of our galaxy like never before. Consequently, we now possess the finest reconstructed image of how our galaxy may appear to an external observer.

Launched on 19 December 2013, the fuel tank of Gaia is now almost depleted – utilizing approximately ten grams of cold gas daily to sustain its precise rotation. Following a few final technological assessments, Gaia will be “retired” by the end of March and relocated to an orbit around the Sun, where it will avoid any potential collisions or disruptive interactions with other spacecraft.

Researchers from several European nations, including Hungary, are engaged in the consortium tasked with processing the data. The origins of this collaboration can be traced back to the 1990s during the era of the Hipparcos satellite, Gaia’s forerunner. “Even back then, it was evident that space-based astrometry would represent a significant milestone in the history of astronomy. This expectation has been thoroughly realized by Gaia,” remarked László Szabados, scientific consultant at the Konkoly Thege Miklós Astronomical Institute of the HUN-REN Research Centre for Astronomy and Earth Sciences (HUN-REN CSFK), who was the initial Hungarian representative in the Gaia consortium.

Over the years, with financial support from the European Space Agency’s PECS and PRODEX initiatives and the Hungarian National Research, Development and Innovation Office – awarded to HUN-REN CSFK researchers László Szabados, Gábor Marton, and Zsófia Nagy – Hungarian involvement has expanded from 3-4 individuals to nearly ten researchers. The inaugural significant contribution from Hungarian researchers to the mission entailed the development of techniques for recognizing Cepheid variable stars. This was subsequently broadened to cover the examination of light variations in younger stars and the monitoring of Gaia’s scientific alerts in response to unforeseen events. To date, as part of the data releases, two papers have been published under the leadership of HUN-REN CSFK researchers László Molnár and Gábor Marton.