Skygazers, mark your calendars because one of the coolest celestial events is coming around again toward the end of February.

Learn about the bright streaks that may represent recent geological activity on Mercury, which has been considered a dead ...

Advances in technology have reopened the debate over terraforming Mars, shifting it from an impossible dream to a long-term scientific and ethical question.

These icy bodies orbit the sun just like the major planets, yet they follow their own rules, often traveling along elongated ...