The European space telescope Gaia, which revolutionized the knowledge of the Milky Waywas out of service this Thursday, after a fruitful life of discoveries that will feed the investigations of astronomers for decades.
Run on December 19, 2013 by the European Space Agency (ESA), Gaia made its observations from a stable orbit to 1.5 million kilometers from the earth, at the point of Lagrange L2.
To prevent, once inactive, it threatens other instruments that work in that place, such as James Webb or Euclid space telescopes, the engineers of the European Space Agency sent Gaia the last orders on Thursday.
Its engines received the order to boost it to an “withdrawal orbit” around the sun, with the guarantee that it will remain at least ten million kilometers from the earth for the next hundred years.
Over eleven years, this galactic eye allowed to create a true map of the galaxy and allowed to better understand its origin, its evolution and its current form.
Gaia allowed to elaborate a catalog of more than 1.8 billion stars, whose positions, characteristics and movements reveal their history.
A study last year identified two groups of primitive stars, in the heart of the galaxy, which would have given rise to their formation more than 12,000 million years ago.
Astronomers also discovered that it later grew and increased by absorbing other galaxies, including a gaia-ocean call, 10,000 million years ago.
And that continues to grow, slowly tearing to this day the dwarf galaxy of Sagittarius.
Experts understand Now better how the matter is distributed in the Milky Way, which has at least 100,000 million stars.
The telescope has also observed the so -called local group, populated by more than fifty galaxies and star clusters.
Gaia has also registered the trajectories of 150,000 asteroids in the Solar System and the presence of several dozen black holes on the Milky Way.
“Very difficult to disconnect them”
On Thursday, Gaia’s mission threw the curtain with a series of commands transmitted from the European Space Operations Center in Darmstadt (ESOC), in Germany.
The engineers disconnected one by one all the redundancy systems originally designed to allow the telescope to survive the dangers of space, such as radiation storms or micrometeoritic impacts.
“The spacecraft are designed so that they cannot be easily turned off, it is very difficult to disconnect them”, Explained Tiago Nogueira, ESA Operations Engineer, at AFP.
The ESOC team turned off Gaia’s instruments before expressly finding out their software on board, and finally deactivated its communication module and its central computer.
The exploitation of the flood of data transmitted by the machine is far from finishing.
The mission will normally deliver its fourth catalog of heaven in 2026, prepared with the first five and a half years of the mission.
The final catalog, with ten and a half years of observations, is expected by 2030.