What is the faint young sun paradox?

Will a man-made meteor shower open the Tokyo Olympics?

Huge 400-foot tsunamis once washed over Mars

An asteroid 18 miles wide slammed into Earth 3.4 billion years ago

Pluto is so unique that science is having trouble classifying it

How will astronauts use augmented reality glasses?

3 new Earth-like planets just 40 light-years away might contain life

Wolf-Rayet stars live fast and die hard

Amazing photo of moon shows off the 'earthshine' effect

Walk down memory lane with Hubble's greatest hits

Why is this doctor living in lonely Antarctica?

Meet the 3 African-American female scientists who helped launch the space race