New images of a nearby dwarf galaxy have revealed a dense stream of stars in its outer regions, the remains of an even smaller companion galaxy in the process of merging with its host. The host galaxy, known as NGC 4449, is the smallest primary galaxy in which a stellar stream from an ongoing merger has been identified and studied in detail.

Although the tyrannosaur made news, other fossils sold at auction may also have been looted.

Paleontologists have a simple reason to believe the fossils came illegally from Mongolia.

The dinosaur tentatively sold at auction is known as Tarborsaurus to most scientists.

Opportunity was perched at the rim of Mars' Endeavour Crater when it took the picture.

Researchers are trying to understand the origins of the beautiful planetary nebula Sharpless 2-71.

Decades of rigorous research, testing and development performed in the Entry Systems and Technology Division at NASA's Ames Research Center, Moffett Field, Calif., has garnered Ames' thermal protection engineers the respect of not just other government agencies, but also commercial entities. The successful re-entry in late May or early June ...

We’ve all heard earthquakes described in terms of their magnitude number. But what does this scale really mean? This video illustrates the variation of energy released in easy-to-understand terms.