Happy International Year of Astronomy! Capitalizing on the fact that 2009 marks the 400th anniversary of Galileo’s earliest telescopic forays into the night sky, the International Astronomical Union ...

Observing the phases of Venus helped Galileo conclude that planets in our solar system orbit the sun, not the Earth. Credit: Creators.com illustration Ask your friends and neighbors, and most will ...

If you peer at the sky during a cloudless dawn or dusk, you'd immediately spot Venus. Appearing as a brilliant, steadily shining speck, it's the second-brightest object in the night sky after the moon ...