ESO has released a ginormous 9-gigapixel image of 84 million stars taken via the VISTA infrared survey telescope at its Paranal Observatory. Featuring the center of the Milky Way, this huge picture is the by-product of an international team of astronomers, and will be used to help study our galaxy. Just how big is 9-gigapixels? Printed “with the resolution of a typical book,” it would be almost 30 feet long and 23 feet high.
Roberto Saito, the lead author of the study, had this to say: “By observing in detail the myriads of stars surrounding the centre of the Milky Way we can learn a lot more about the formation and evolution of not only our galaxy, but also spiral galaxies in general.” Spiral galaxies feature their oldest stars in the center, something astronomers call the galaxy’s bulge. Seeing the Milky Way’s bulge is difficult because of copious amounts of dust.
According to the study’s co-author Dante Minniti, astronomers have to observe infrared light when dust is an issue. To get this image of our galaxy’s middle, the team used VISTA, which stands for Visible and Infrared Survey Telescope for Astronomy. The team used data from VISTA Variable in the Via Lactea program to assemble the mega image.
This is the first time the Milky Way’s bulge has been cataloged like this, containing ten times the number of stars of previous efforts. Said Minniti: Each star occupies a particular spot in this diagram at any moment during its lifetime. Where it falls depends on how bright it is and how hot it is. Since the new data gives us a snapshot of all the stars in one go, we can now make a census of all the stars in this part of the Milky Way.”