Giant ice towers that formed next to steaming volcanic vents in the freezing atmosphere of Mars may be the best place to look for life on the Red Planet, an Australian geologist said Monday.
Nick Hoffman of the University of Melbourne said the latest images taken by the Mars Odyssey orbiter had revealed curious hot spots in the Hellas Basin that could be similar to ice towers in Antarctica, where microbial life forms live on chemical energy.
These hot spots, he told Reuters, could prove a better place to find signs of life than gullies that some speculate may have been gouged by running water.
“I don’t personally believe that that (finding life) is a credible possibility, but nonetheless, if you are going to find life on Mars, this is probably the place it will be,” he said.
Hoffman has worked on potential Mars ice towers with Professor Phil Kyle of the New Mexico Institute of Mining and Technology in the United States.
Their research, based on NASA imagery and the study of the Mount Erebus volcano on Antarctica’s Ross Island, was presented at the Sixth International Mars Conference in Pasadena, Calif., in July.
On Ross Island, steam from volcanic vents is converted directly into ice as it touches the frigid air, building tall, hollow chimneys where a microclimate allows bacteria to live.
“On Mars, similar structures could be doubly valuable for potential Mars microbes,” Hoffman said, dubbing the prospect of finding life on the planet “a remote possibility.”
NASA’s latest Mars mission, carrying two rovers to probe for signs that conditions on Mars once favored life, will not go anywhere near Hellas Basin, a deep impact crater about the size of Australia in the Red Planet’s southern hemisphere.
Nor will the European Space Agency’s Mars Express, which blasted off in June.
Scientists hope the two expeditions, plus a Japanese mission, will find evidence that liquid water once existed on Mars and may have left long gullies or channels in the inhospitable terrain.
Hoffman said infrared images taken by the Odyssey showed the hot spots in the Hellas Basin — laid out in a chain — were hotter than the surrounding environment both during the day and at night.
Once the Odyssey’s companion satellite, the Mars Global Surveyor spacecraft, takes high-resolution images of the formations in clear light, it will be possible to identify them definitively as ice towers or something else.
Hellas Basin is the deepest part of Mars and has the highest air pressure, a prerequisite for liquid water. Elsewhere, the planet’s atmosphere is so thin that water cannot form, so heated ice is likely to become vapor, missing out the liquid phase.
“There will not be a convenient hot spring of liquid water flowing on the surface, but there will be a steamy, moist vent in the ground with a lot of ice present and possibly an ice tower,” Hoffman said.