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first_imgThe European Space Agency (ESA) launched the Gaia spacecraft in 2013 with the aim of creating the most complete map ever of the Milky Way galaxy and other nearby objects. It began observing the sky in 2014, and now the first block of Gaia data has been released by the ESA. It includes location data on more than 1.1 billion stars in the Milky Way.Gaia carries a number of instruments that it uses to capture gigapixel images of space. More than 40GB of data is collected by the probe every day, which is used to create the galactic map. This data release includes the precise position and brightness of 1.142 billion stars. The data is accurate to within 300 microarcseconds — the apparent width of a human hair from 30 kilometers. Gaia has also collected distances and motion data on a further 2 million stars in addition to the position and brightness data. This is still only a small part of the Milky Way, which has 100-400 billion stars.All of this data is available for download, so scientists all over the world can conduct research on the structure of our galaxy. With a few more years left in the Gaia mission, there will be more data dumps from the ESA too. The next data set (planned for late 2017) will include even more precise location data for stars, in the range of 10 microarcseconds (the apparent width of a human hair from 1000 kilometers). Astronomers expect Gaia to discover hundreds of new star clusters in the Milky Way when that data is assembled. We might even be able to pin down that 100-400 billion number of total stars in the galaxy.Depending on the success of the initial five-year mission, the ESA may choose to extend Gaia’s operational life through 2024. The ESA also envisions a successor to Gaia that could launch in the mid-2020s. This spacecraft would use infrared instruments to peer through the thick dust and gas toward the center of the Milky Way.last_img read more