When it is summer in the north, it is winter in the south. The southern polar cap of this mystery planet is defrosting because summer arrived in its southern hemisphere in December 1999. It's bedtime at the south pole as Spring begins in the northern hemisphere. Read this article to learn about today's autumnal equinox on Earth and seasons on other planets in the Solar System. As southern summer approaches, the south polar cap of Mars is melting in a bizarre pattern that looks like Swiss Cheese.
Asteroids have seasons, too.
You can watch the sun go down at the South Pole thanks to a web cam at the Antarctic Astrophysical Site Testing Obsrvatory. Click here for a larger image and for realtime views of the South Pole. Requires Shockwave . In Antarctica the sun is about to set for a long winter night. The darkness will last for nearly six months at the south pole, which is good news for many astronomers who have established remotely operated telescopes there.