9-gigapixel image shows 84 million stars

The European Southern Observatory (ESO) has released a massive picture of the heart of the Milky Way Galaxy.

This is incredible. Taken by the Visible and Infrared Survey Telescope for Astronomy (VISTA) at the ESO's Paranal Observatory in Chile, this 108,500x81,500-pixel image is an interesting case study for Olbers' Paradox. Containing nearly 9 billion pixels — so large that if it were printed at the resolution of a standard book, it would measure 9x7 metres — it comprises thousands of stitched-together images taken using VISTA's infrared camera at three different filter settings.

The infrared camera cuts through things like dust fields, allowing the image to show stars that would be obscured in a normal spectrum view.

Although it claims to show 84 million stars, we're not entirely sure how they were counted. The photo was taken in order to study the Milky Way Galaxy central bulge, and will help astronomers to understand the formation and evolution of galaxies.

You can view the full image here, as well as wallpapers (see the bar down the right-hand side) on the ESO's website.