The NASA/ESA Hubble Space Telescope a new space wallpaper image of the Antennae Galaxies.The galaxies — also known as NGC 4038 and NGC 4039 — are locked in a deadly embrace. Once normal ...

The northwestern part of Greece is pictured in this space wallpaper by the Landsat-8 satellite. The Ionian Sea dominates the left side of the image, with the Ambracian Gulf near the center.

As to why Microsoft is charging 99 cents for the pack it is likely to do with licensing. Last I checked, Microsoft is not operating a deep-space telescope, and such images in 4K are rarely free ...