The comet is one of only three of its kind recorded in history. But others think there could be more to this celestial object ...

What is the biggest object in the universe? Learn more about the biggest objects in the universe, including galaxies, galaxy clusters, and dark matter.

A full moon is slated for Sept. 7, but there are other celestial events occurring this month. More on viewing Saturn at its ...

"I think it's natural to take a break and wonder whether we are fundamentally thinking about this in the wrong way." Dark matter could be made from tiny black holes formed when so-called "dark baryons ...