Polar Regions - page 5

The Devon Island Analog

In the Canadian High Arctic, scientists have found a location where surface conditions are very similar to those on Mars. Although no place on Earth is exactly like Mars, due to differences in atmosphere, gravity, and temperature, planetary researchers look for Earth locations where environmental conditions and geologic features simulate Martian conditions. These Earth locations are called terrestrial analogs, and they offer scientists the opportunity to conduct fieldwork that will help in planning future studies of Mars.

Devon Island, the largest uninhabited island on Earth, has a unique combination of features that approximate conditions on Mars: an impact crater (Haughton Crater) in a rocky desert; cold, windy conditions; and channels and canyons that resemble many of those observed on Mars.

When water collected in Haughton Crater, lake sediments were deposited. By studying the ancient lakebeds, scientists can learn how to recognize and sample similar places on Mars. In addition, Haughton Crater is home to microbial life that has proven to be very adaptable to extreme conditions, and similar organisms might be found on Mars, given its cold environment.

Researchers' tents sit amidst the grey hills of Devon Island in the Canadian Arctic. The site serves as an excellent location to simulate environmental conditions on Mars. (Image Credit: NASA/JPL/ASU)

Researchers sponsored by the Mars Society are using the environment on Devon Island as a "trial run" for future human missions to Mars, including testing communications systems and robotic technology, and studying human responses to prolonged exposure to extreme conditions. The HMP is a multidisciplinary effort to conduct studies related to geology, hydrology, and biology, and has just completed its ninth field season.

Earth's Polar Regions

Icy Endings

During the 1800s and early 1900s, polar exploration reached a zenith, and fierce competition drove explorers to be the first to reach the poles. But the polar regions were uncharted territory, and many exploration teams were ill-prepared for the extreme conditions they would face in the icy seas. Thus, several expeditions ended in tragedy.

On May 19, 1845, Englishman John Franklin set out with two ships, the Erebus and aptly named Terror, to search for the Northwest Passage. In Titanic-style attitude, Franklin and his Admiralty believed that their voyage could not fail - their vessels were lavishly equipped and their crew was well-trained. But after being spotted by two whaling ships in July 1845, the expedition and its men were never seen or heard from again. The disappearance of Franklin and his men generated much publicity, and between 1848 and 1959, about 40 search expeditions were launched, costing the British and U.S. governments huge sums of money. Despite all the search efforts, the party was never found. Based on traces of the Franklin expedition found by some search parties, it is believed that the two ships became trapped in sea ice near King William Island, forcing the crew into starvation and freezing conditions. Accounts by Inuit natives indicate that the men even resorted to cannibalism to survive. Forensic evidence from three bodies found preserved in the permafrost on Beechey Island, where many of the expedition remnants were found, now suggests that lead poisoning from food stored in tin cans may have also contributed to the party's demise.

In July 1879, U.S. Navy Lt. George Washington DeLong led the USS Jeannette expedition from Siberia to search for the North Pole. In September, the ship became caught in an ice pack near Wrangel Island, and for the next 21 months it drifted northwest towards the North Pole. But on the night of June 12, 1881, the ship finally began to crush under the pressure of the ice, and by the next morning the Jeannette had sunk. With three boats, supplies, and equipment, the men began a difficult trek over the ice in an effort to reach open water - which they eventually did. But the three boats became separated during a storm, and only one boat, commanded by George W. Melville, survived. In 1882, Melville conducted an exhaustive search for the remaining members of the Jeannette party, but his only find was the bodies of 10 fellow expedition members.

Solomon Andree and his crew set sail for the North Pole on their balloon the Eagle on July 11, 1897. Their fate would remain unknown for 33 years. (Image Credit: Andréemuseet, Grenna Museum, Gränna, Sweden)

In 1897, Salomon Andrée of Sweden tried another method of reaching the North Pole: balloon. Although skeptics doubted the ability to keep a balloon aloft that long, Andrée countered that summer conditions would minimize temperature variations, so the balloon's gas would not expand or contract too much. But shortly before their scheduled departure, a leak in the balloon was discovered - one that would cause the balloon to lose about 35 cubic meters of gas per day. Despite warnings, including one from the balloon-maker himself, André, Nils Strindberg, and Knut Fraenke departed on the Eagle on July 11. The balloon was never seen again, and the fate of the men would not be discovered for 33 years. Then in August 1930, a Norwegian fishing boat found relics from the Andrée expedition, including a canvas boat, sled, a cook stove, food, and clothing. The skeletons of Andrée and Strindberg were also found. Most importantly, Andrée's diary was discovered in nearly perfect condition. The journal revealed that three days into the voyage, ice began to weight the balloon down, forcing the team to open the valves and land the balloon. For the next three months, the men trekked over the ice in an attempt to reach land. But all three men perished, and the last journal entry by Andrée was dated October 12, 1897.

Polar Exploration on Earth