What we're seeing in this picture is millions of glowing stars from the brightest part of our galaxy, the Milky Way. A patch of sky so filled with stars that hardly any dark spots are seen across the entire picture. However in the centre, next to an especially bright, blue star cluster, you can see a strange dark cloud. This might look like an empty hole in the backdrop of stars, but this dark patch is actually a small, isolated cloud of dust sitting in front of the star field. We call clouds like this one ’Bok globules'. It is made up of small dust grains that are blocking the starlight from behind and making the region look empty.