Barnard 68 is a dark nebula located in the constellation Ophiuchus. It is notable for its distinct shape and dense concentration of dust and gas, which block light from stars behind it. This makes it one of the most prominent examples of a dark nebula in the night sky. Discovered by E.E. Barnard in 1919, Barnard 68 is approximately 500 light-years away from Earth. Its size is about 1.5 light-years across, and it is part of a larger molecular cloud complex. The nebula is a region where new stars may eventually form as the gas and dust collapse under gravity.