The European Space Agency’s (ESA) Gaia mission has officially ceased scientific operations after 12 years of service. This spacecraft, dedicated to mapping the Milky Way, has exhausted its propellant gas reserves, marking the end of an era ofobservation cosmic.
Credit: ESA/ATG medialab; background: ESO/S. Brunier
Since its launch in 2013 and positioning at the L2 Lagrange point, Gaia has revolutionized our understanding of the Milky Way. By studying nearly 2 billion stars, it provided data valuable on their movements, luminosity, temperatures and compositions. This information has building permit the most detailed 3D map of our galaxy.
Despite the end of sightings, Gaia’s legacy is far from over. Scientists are already preparing the fourth data publication (GR4), expected before mid-2026. This version promises to be even richer in information than previous ones, with observations spanning five and a half years.
Processing of the data collected by Gaia will continue until the 2030s, with a fifth and final publication planned. This final phase will include a decade of stellar observations, providing a goldmine for future research in astronomy.
Crédit: ESA/Gaia/DPAC/Gaia Flight Operations Team.
ESA plans to soon share details about Gaia’s ‘passivation’ and how this pioneering mission will be commemorated. In the meantime, the scientific community continues to exploit Gaia’s data, promising discoveries in the years to come.
What is the L2 Lagrange point?
The Lagrange point L2 is a position in space where the gravitational forces of the Earth and the Sun balance, allowing an object to maintain a stable position relative to these two bodies. Located approximately 1.5 million kilometers from Earth, it is ideal for space telescopes like Gaia, because it offers a clear view of the Universe without interference land.
This point is particularly popular for astronomical observation missions, because it allows continuous observation without the interruptions caused by the Earth’s shadow. Additionally, gravitational stability reduces the need for frequent trajectory corrections, thereby saving time. fuel.
-Gaia’s use of the L2 point enabled precise and continuous observations, contributing to the creation of the most detailed 3D map of the Milky Way. This strategic position was crucial to the success of the mission, maximizing the quality and quantity of data collected.
How has Gaia revolutionized our understanding of the Milky Way?
Gaia has transformed our understanding of the Milky Way by providing precise data on nearly 2 billion stars. This information includes stellar movements, luminosities, temperatures and compositions, allowing scientists to reconstruct the history and structure of our galaxy.
The mission created the most detailed 3D map of the Milky Way, revealing unprecedented details about the distribution and movement of stars. These data have also made it possible to identify binary star systems and black holes, enriching our knowledge of celestial objects.
Observations of Gaia have also contributed to the study of dark matter and galactic evolution. By mapping stellar motions, scientists can better understand the gravitational forces at play and the distribution of dark matter in the galaxy.
Finally, Gaia’s data will continue to be exploited for decades, promising new discoveries and a better understanding of our place in the Universe. The mission thus laid the foundations for future space explorations and astronomical studies.
