Users on social media said they spotted comet Atlas over Pennsylvania skies early evening on Thursday. Photos of the comet ...

Comet Tsuchinshan-ATLAS, which has arrived from the edge of the solar system, was observed from various parts of Japan ...

After months of waiting, a comet the could prove to be bright enough to see with the naked eye and even during the day from the northern hemisphere, has arrived — and the first photos are in.

This long-period comet from the Oort Cloud — a sphere around the solar system home to millions of comets — astronomers think it loops around the sun once every 80,000 years. Also known as ...