Journal Entry

Yes, it is true. But never stare at the Sun! Its rays can cause permanent, incurable blindness.

The South Pole experiences six continuous months of daylight, when the Sun is above the horizon, and then six months of either twilight or darkness, with the sun below the horizon. The Sun will be visible only from September 23 to March 21 (the austral spring and summer), and it remains hidden between the equinoxes, from March 21 to September 23 (the austral autumn and winter). Seasons are reversed in the northern and southern hemispheres, so the austral summer --when most work is done at the South Pole-- corresponds to the North American winter and vice versa.

The reason why the planet goes through seasons lies in the fact that the Earth's rotation axis is not aligned with its orbit around the Sun. The earth's equator is inclined by 23 degrees with respect to the ecliptic. So, around the solstice on December 21 the Sun will reach --as seen from the South Pole-- its maximum yearly elevation of 23 degrees above the horizon. The Sun will actually move in the sky along the day, but will do so horizontally, not vertically, running parallel above the horizon. The actual solar elevation will rise from 0 to 23 degrees from September to December, and then down to 0 again from December to March. Sunset and sunrise occur just once a year, in March 21 and September 23, respectively

In essence, there are only two true seasons at the poles: day and night. A month-long twilight, of course, occurs before sunrise and after twilight. So, the six month polar 'night' is actually made up of about four months of full darkness plus two months of twilight.

The following link shows an Adobe Flash animation that helps visualize everything that has been explained here.

Compare the Poles: Seasons http://polardiscovery.whoi.edu/poles/seasons.html