100 years--and counting--at the South Pole (photos)

Wednesday marks the 100th anniversary of explorer Roald Amundsen becoming the first to reach the South Pole. In this image Amundsen, Helmer Hanssen, Sverre Hassel and Oscar Wisting (left to right) are pictured at "Polheim," the tent erected at the South Pole on December 16, 1911. The top flag is the Flag of Norway; the bottom is marked "Fram."
Amundsen disappeared aboard a French Latham 47 flying boat in the Barents Sea on June 18, 1928. The plane had been searching for the gas-filled airship "Italia," which crashed when returning from the North Pole during an expedition led by Italian aeronautical engineer Umberto Nobile.

The base at Framheim, February 1911.

Over the decades, scientists and support personnel have conducted research at the South Pole on myriad projects. But the conditions are anything but balmy as evidenced by this 1960 photo. The ice sheet below South Pole is nearly two miles thick.

A C-124 Cargo plane airdrops lumber to U.S. Navy Seabees at the South Pole, December 1956 as they went about the construction of a research station.

A December 4, 1956 aerial view of the first permanent station at the South Pole.

This C-47 was the first airplane to land at the South Pole on October 31, 1956.

Group shot of the U.S. Navy Seabees who built the first South Pole station. Work was completed in late December 1956.

Today the South Pole Telescope collects data on cosmic microwave background radiation and black matter.

The South Pole offers six months of constant sunlight for studying the sun. This 1985 image shows researcher Martin Pomerantz at the Pole.

Weather balloons launched at Amundsen-Scott South Pole Station. The base was named in honor of two explorers. Norwegian Roald Amundsen led the first successful expedition to the South Pole 100 years ago. The other half of the base's name was in memory of British explorer Robert Falcon Scott, who lost the race against Amundsen and arrived at the South Pole more than month later, only to find Amundsen's tent, a Norwegian flag and a letter from Amundsen. Scott and four companions died on the way out.

Dome of the South Pole Station, which was completed in 1975.

1993 overhead shot of the geodisc dome and support tunnels at the South Pole Station.

The entrance to the dome filled up with snow and ice accumulation, as demonstrated in this 1975 photo. It ultimately required the digging of an access tunnel.

Korean War vintage Jamesway huts.

U.S. flag, backlit by Southern Lights, flies at half staff in June 2004 in memory of former President Ronald Reagan. The flag was also lowered after the 9/11 terror attacks and the Space Shuttle Columbia loss in 2003.

No longer any need for roughing it. A look at the base recreation room.

Isolation of the U.S. South Pole Station. The nearest human habitation is McMurdo Station on Ross Island, about 900 miles away.

2008 ceremony including the 12 original signatory nations of the Antarctic Treaty.

July 2005 image taken during the 6-month-long Antarctic night.

Aerial photo taken in 2005 of new South Pole Station. The older station is at lower left

South Pole Infrared Explorer was used to probe areas where new stars form by recording their infrared emissions.

Atmospheric Research Observatory tracks changes in the Earth's atmosphere.

Tumbleweed rover is an experimental device designed to land on other planets. In 2004 tests, it has traveled more than 40 miles around the pole.