For astronomers studying dark matter, the Bullet Cluster is one of the greatest laboratories in the universe. Follow-up ...

A swarm of galaxies called the Bullet Cluster is the biggest, best natural laboratory for studying dark matter that ...

May the faint chemical signals drifting through the atmosphere of a distant world be the long-sought message that we are not alone. Astronomers have reported seeing an unusual and strong combination ...

One of the best places to study stars is inside "open clusters," which are groups of stars that formed together from the same material and are bound together through gravity. Open clusters act as ...