A section of the 1.7-gigapixel image of the Milky Way created by Finnish astrophotographer J-P Metsavainio. (Image credit: J-P Metsavainio)
Finnish astrophotographer J-P Metsavainio spent 1,250 hours over the course of about 12 years creating a single image that reveals the magnificent beauty of the entire Milky Way galaxy.
Back in 2009, Metsavainio began this project, which is a 1.7-gigapixel mosaic of the Milky Way composed of 234 individual images all stitched together. The resulting image (which you can see below) captures the entire galaxy, speckled with about 20 million of the Milky Way's roughly 200 billion stars.
So, how could a single image take 12 years?
In his blog, Metsavainio points to "the size of the mosaic and the fact that the image is very deep. Another reason is that I have shot most of the mosaic frames as individual compositions and published them as independent artworks." In the blog, Metsavainio also includes information about the different cameras and some of the more specific techniques he used to create this image.
Some of the celestial objects in the Milky Way required more exposure than others, as some appeared dimmer and were harder to see. For example, a single supernova remnant took over 60 exposure hours, he explains in his blog.