The European Space Agency's Gaia spacecraft has been surveying the sky since 2014, and data gathered from its observations helped create a catalog of more than 1 billion stars around our galaxy.
ESA on Wednesday, Sept. 14, released what to date is the most detailed 3D map of a billion stars in the Milky Way. The newly released data include details on the position and brightness of 1.142 billion stars along with the motions and distances of more than 2 million stars.
Gaia, which was launched in December 2013, has been snapping images of the Milky Way. The space probe's billion-pixel camera is the largest ever launched in space. This camera is so powerful it is capable of gauging the diameter of the human hair 1,000 kilometers away, which means that the nearby stars Gaia observed were located with unprecedented accuracy.
In less than three years after Gaia's' launch, the satellites' two telescopes have already located a billion stars. The first catalog of the Milky Way's billion stars is based on data that Gaia collected during the first 14 months of its scientific work scanning the sky, which started in July 2014.
The number of stars Gaia has located is only 1 percent of the estimated stellar population in the Milky Way, but astronomer Francois Mignard, who is part of the Gaia science team, said that this is enough to keep professional stargazers busy for years.
The data gathered by Gaia was crucial to development of the impressive 3D catalog of the Milky Way, but the space probe was not constructed solely to chart the locations of stars. It was also made to track stellar movements.
Over the course of its five-year mission, Gaia will conduct observations of each of its over-a-billion targets about 70 times, which could help astronomers track the changes in the position and brightness of stars over several years.
Gaia's observations could provide important information that could help shed light on the properties and evolution of the Milky Way. Knowing the history of our galaxy provides crucial information to better understand the universe. Gaia's data may even help scientists calculate the rate at which the universe expanded since the Big Bang.
"Gaia's present and future data will revolutionise all areas of astronomy, allowing us to investigate our place in the Universe, from our local neighborhood, the Solar System, to Galactic and even grander, cosmological scales," said Anthony Brown from Leiden University in the Netherlands.