One of the brightest galaxies in planet Earth's sky and similar in size to the Milky Way, big, beautiful spiral M81 lies 11.8 million light-years away in the northern constellation Ursa Major. This...

Our Sun has become quite a busy place. Taken only two weeks ago, the Sun was captured sporting numerous tumultuous regions including active sunspot regions AR 2036 near the image top and AR 2036 near the center.

On July 20, 1976, NASA's Viking 1 lander become the first spacecraft to land on Mars, followed weeks later by its twin robot explorer, the Viking 2 lander. Operating on the Martian surface...