Sunrise at the South Pole

The Sun Only Rises Once A Year and Sets Only Once A Year

September 23, 1999: Every year about this time thousands of penguins rejoice to see the sun peep above the horizon in Antarctica. The return of the sun after 6 long months of chilly darkness means spring has arrived. For penguins it's time to shed a few pounds of blubber, find a mate, and bask in the sunshine for the next 6 months. For a small band of scientists and technicians who wintered over at the South Pole, it's time for supply drops, mail, and fresh fruit. Outside the temperature begins to climb from a frigid -70 deg. C to -25 degrees. Spring is in the air. What triggers this South Pole revolution? It's called the autumnal equinox.

The Automated Astrophysical Site-Testing Observatory near the US South Pole Station captured by a web cam just 2 days before 1999 autumnal equinox. The reddish-pink dawn sky presages the coming of a 6 month-long day. Click for images updated every 10 minutes. On the day of the equinox sunlight and darkness are of almost equal length. At the South Pole the sun rises, and at the North Pole it sets for six months.