ESA's Gaia space telescope to be deactivated on Thursday
Gaia has collected data on billions of stars for more than ten years and will take years to analyze. It will be switched off on Thursday.
Artist's impression of the space telescope in front of the Milky Way
(Image: ESA - D. Ducros)
ESA's revolutionary Gaia space telescope will finally be switched off on Thursday. Gaia will then receive its last commands from the ESA Satellite Control Center in Darmstadt, the Gaia team announced a few days ago. Previously, the space telescope was rotated at the beginning of March so that it reflected significantly more light back to Earth and was photographed by several amateur astronomers around the world. Now Gaia will remain "dark forever", the research work is finished. However, the data collected will continue to be analyzed for a long time, with further data sets to be published in 2026 and 2030.
"Spectacular results"
Gaia has "redrawn the entire picture of the Milky Way", says mission manager Uwe Lammers, explaining the significance of the instrument to dpa: "We are creating the most accurate map of the galaxy that has ever been produced", says Lammers. "In the beginning, for example, the mission was designed to observe one billion stars. Now there are two and a half billion." Although much was already known about our home galaxy beforehand, the space telescope really has discovered so much new information. For example, traces of a collision with a dwarf galaxy 5.7 billion years ago were discovered, which may even have led to the formation of our solar system: "That is one of the most spectacular results."
Before Gaia, it was assumed that the Milky Way was smooth and flat, Lammers continues. Now we know that it is bent at the edges and that all parts are constantly moving. Thanks to the space telescope, it has also been discovered that there are many more black holes in our cosmic neighborhood than previously assumed. Gaia has found several comparatively close ones and the data sets still expected could conceal more or even exotic, previously unknown types of celestial bodies. The scientist also expects the discovery of many more exoplanets from the publications.
Gaia was launched at the end of 2013 and was considered to be perhaps the most important telescope in space six months after it began its scientific work. Using a gigapixel camera, it continuously photographed the night sky for more than ten years. As it moved around the sun with the Earth, the precise measurement data made it possible to determine the position of billions of stars with increasing accuracy thanks to the so-called parallax measurement. The instrument was thus able to lay the foundations for a wide range of further research. Now, however, the fuel has run out and the device has to be deactivated.
Retirement "well deserved"
The space telescope needs its fuel to keep itself precisely aligned in space. Every day, around 12 grams of cold gas are lost and the supplies would be completely used up by the end of the year. Instead, however, it was decided to stop the research and use the remaining fuel to carry out weeks of tests on the spacecraft, which could help with the design of a successor. The spacecraft then left its location at Lagrange point L2 and is to enter a final heliocentric orbit with a final thrust on Thursday. It will then be deactivated in such a way that it does not reactivate and can begin its "well-deserved retirement", as the ESA has put it.
(mho)