Life in Extreme Environments: The Chilean Desert and the South Pole, and Maybe Mars

March 1, 2016

Astrobiologists have been studying extreme environments on Earth as analogues of the conditions life would face in space, particularly, on Mars. It appears certain now that Mars has at least the key prerequisites for life to thrive, with the likelihood of at least some liquid water beneath the surface, carbon in its atmosphere, and sunlight. But the intense radiation bombarding the surface may have driven life underground, where rock-eating extremophiles thrive on chemisty, without photosynthesis.

Chile's Atacama Desert, described as "the driest place on Earth," has been the site of many studies of life in extreme environments. There, the dryness and ultraviolet radiation levels are similar to Mars. Assuming that any extant life on Mars is most likely underground, the current experiment, the Atacama Rover Astrobiology Drilling Studies (ARADS), has completed its first month of fieldwork, and has drilled down to 2.2 meters to take samples. These will later be analyzed in a laboratory, to see if any life exists there.

The goal is to test a Mars-prototype drill, an arm to transfer samples from the surface, which would be brought back to Earth, the Signs of Life Detector, contributed by Spain, and a prototype version of the Wet Chemistry Lab, to do an in situ chemical analysis. More than 20 scientists are participating, from the U.S., Chile, Spain, and France.

Farther south, China is carrying out a series of experiments to enable human life to thrive on Mars, on one of its four Antarctic stations, testing hydroponic technologies for growing vegetables. Currently, food is brought to the Chinese stations by ship once a year, which takes 75 days, covering 18,000 miles.

"In 'The Martian,' Mark Watney is a botanist, but I am a surgeon," joked Wang Zheng, responsible for the experiment, while being the medic. He reports that during his year at the station, he was able to germinate lettuce seeds in three days, and harvest fresh lettuce one month later, Xinhua reported Tuesday.

Yu Wanxian, who is a guest professor with the China Polar Research Center, and wrote the guidelines on nutrition for the Antarctic expeditions, said that this "vegetable nursery" puts China in the forefront of polar research. The nursery will be expanded, with the government's approval of a $1.5 million budget. Wang reported that the fresh vegetables are so popular, foreign teams are always happy to accept an invitation to dinner at the Chinese station.

In addition to developing the technology to grow food off planet, important in itself, it has also been promoted for on-planet applications. For example, taking the soon-to-be-empty skyscrapers in Manhattan, and using hydroponics, all the fresh fruit and vegetables could be grown for New Yorkers (rather than stealing them from Mexico).