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This is actually a spacecraft/mission that I see almost never mentioned here on the forums for some reason... yet it has been quietly working away at its task, and now, the first results are in. ESA's Gaia spacecraft, sometimes nicknamed the Billion Star Observatory, is an astrometry satellite launched in 2013 and currently sitting at Earth-Sun L2. it has now returned enough data for a new map of the Milky Way to be published. A map made out of 1,142,000,000 stars, in full 3D, each with its position and its brightness determined with extreme precision. It is the largest all-sky survey ever performed in the history of mankind... and Gaia is only 14 months into its 5-year primary mission. Because Gaia wants to do more than just position and brightness. It wants to map relative movements and distances, too. Already, two million stars have their relative movements characterized in the current dataset, but that's just the beginning. With each month that passes, more and more stars will reach the point where there's enough data to derive their movements from. Also, Gaia is expected to chance across tens of thousands of previously unknown exoplanets, comets, qasars and other astronomical objects along the way. Needless to say, a lot of astronomers are very excited by this. Now, some disclaimers: Gaia cannot map the entire Milky Way, due to being inside it - a lot of the galaxy actually blocks itself from view. Additionally, there are limits to the minimum brightness of stars that it can reliably track. In fact, it is expected that Gaia will map "only" around 1% of the entire contents of the galaxy. I say that in quotation marks, because that's still far more than any other single instrument has ever detected.