Searching for signs of life on Mount Everest could provide a window into the extreme environments that organisms might inhabit elsewhere in the universe.
So, former astronaut Scott Parazynski will set up instruments to hunt down elusive evidence of life at the top of the world when he attempts to summit Everest Wednesday.
Parazynski, a veteran of five space shuttle flights, has also been a life-long climber. Parazynski left NASA in March, just before departing to Everest.
"I've been dreaming of an ascent of Mount Everest ever since I began dreaming about space as well," Parazynski told SPACE.com.
In fact, the two dreams hold a similar appeal. "When you stand in a place that very few others can go, it's really a neat accomplishment," he said. He and his climbing team first planned to try to reach the summit earlier this month, but weather postponed their attempt.
During this trip, Parazynski is combining his two passions of space and climbing by conducting astrobiology research.
"We're looking for evidence for life in the extreme," he said. "Things that can live in the harshest environments on Earth may be the kinds of things that once existed on Mars or other planets."
Living organisms have been found in some of the most trying environments on Earth, such as highly acidic lakes, deep mines and dark, cold underwater depths. So there's a chance that life also exists on the frigid, oxygen-deprived peaks of the Himalayas.
In collaboration with scientists at NASA's Ames Research Center in California, Parazynski has planned a series of experiments to conduct on the mountain to hunt for signs of extreme life, called extremophiles. For instance, he hopes to find lichen, algae and bacteria on the rocks at the tallest mountain in the world.
Parazynski also brought along devices to measure the surface temperature of rocks, as well as their exposure to ultraviolet radiation, which may be so high at such a lofty altitude that many life forms would be unable to survive. He plans to deploy DNA samples at various sites and then retrieve them to determine in the lab how much ultraviolet radiation they were exposed to.
"Ultraviolet radiation is a key parameter in the sustenance of life," Parazynski said. "But too much, of course, and everybody gets skin cancer and it affects plankton blooms. We'll be up at those altitudes at the peak of UV penetration, and we'll be able to assess the amount of ultraviolet damage taking place."
He'll also leave sensors on rocks to detect whether any liquid water exists at any time during the day, or if ice and snow simply sublimate to vapor without passing through the liquid phase.
"If water does exist in certain areas, then life can form there," Parazynski said.
The astronaut may even leave some sensors and equipment behind when he descends, to let the instruments collect data and transmit it back to scientists throughout the year.
Though scientists have previously conducted some geology and ecology research at Mount Everest, Parazynski's work may be the first attempt to do astrobiology there. If he gets really lucky, he may even find some fossilized remains of life on the crag to bring down for his research team to analyze.
Parazynski almost became the first astronaut to summit Everest one year ago this month when he ruptured a disc in his back. He decided not to push through the pain and returned to base camp. Since then, he has had back surgery.
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