The Mars Odyssey probe has found possible entrances to underground caves on the Red Planet. One might be hundreds of feet deep and they all might lead to protected oases in which life may once have found shelter from the bitter cold and radiation-hardened conditions on the surface.
The images on the left show a scene partway up Mars’ number two mountain. In B, the slightly darker patch shows cool air in the hole. The nighttime view of C shows it is much warmer in the hole than the surrounding landscape.
The football-field sized holes were observed by Mars Odyssey’s Thermal Emission Imaging System (THEMIS) and have been dubbed the seven sisters –Dena, Chloe, Wendy, Annie, Abbey, Nikki and Jeanne–after loved ones of the researchers who found them. The potential caves were spotted near a massive Martian volcano, Arisa Mons. Their openings range from about 330 to 820 feet (100 to 250 meters) wide, and one of them, Dena, is thought to extend nearly 430 feet (130 meters) beneath the planet’s surface.
Even though Mars is farther from the sun than Earth, radiation is a hazard to life because of the total lack of protection from an ozone layer or a radiation belt. (At least for the moment, Earth has both.) Caves might be convenient locations for future bases on the planet. Plus, there may be some very interesting stuff down there. I’m not holding out serious hope for life on Mars, even fossils, but the geology must be fascinating.
If any Republicans are planning to dodge climate change by setting up ski resorts on Mars, they might want to think again. The ground under their feet may be as shaky as it is in Washington these days.
Every spring brings violent eruptions to the south polar ice cap of Mars, according to researchers interpreting new observations by NASA’s Mars Odyssey orbiter.
Jets of carbon dioxide gas erupting from the ice cap as it warms in the spring carry dark sand and dust high aloft. The dark material falls back to the surface, creating dark patches on the ice cap which have long puzzled scientists. Deducing the eruptions of carbon dioxide gas from under the warming ice cap solves the riddle of the spots. It also reveals that this part of Mars is much more dynamically active than had been expected for any part of the planet.
“If you were there, you’d be standing on a slab of carbon-dioxide ice,” said Phil Christensen of Arizona State University, Tempe, principal investigator for Odyssey’s camera. “All around you, roaring jets of carbon dioxide gas are throwing sand and dust a couple hundred feet into the air.”