Scientists discover liquid water 'lake' on Mars

Scientists discover liquid water 'lake' on Mars

For years, mankind has dreamed of visiting our second-closest neighbor, Mars. Personally, I don't get it. The Red Planet is a frigid, barren landscape. It looks miserable. I'd much rather visit a beautiful location on Earth, like Hawaii, Australia or Iceland.

But still, the idea of extraterrestrial life is fascinating. And it would be nice a back-up planet if we totally trash Earth. Out of all the other planets in our solar system, Mars is the most habitable. The gravity is 38% of Earth's, the Mars day is roughly 24 hours and 40 minutes, and the rocky soil contains water to extract. Last January, NASA announced they found vast reserves of subterranean frozen water ice. And now the journal Science reports that researchers may have discovered something remarkable on the Martian surface.

Mars lake Credit: NASA

By using Marsis, a radar instrument on board the European Space Agency's Mars Express orbiter, scientists appear to have identified a 12-mile underground lake. They spotted ephemeral water flowing on the planet's surface before, but not a persistent body of water. The reservoir is located underneath the south polar ice cap, composed of freezing, briny water and is speculated to be a minimum of three feet deep. It is wide, but shallow.

According to the study, the water is thought to be 26 degrees Fahrenheit at the warmest, which is below freezing. The high amount of salt lowers the water's freezing point, which is how it remains liquid in such extremely cold conditions. It's possible the temperature could get as cold as 70 degrees below Fahrenheit. But this frigid, briny extraterrestrial water could sustain microbial life. It could potentially also be filtered and made pure for human consumption.

Radar detecting a lake on Mars Credit: ESA

Marsis provides good evidence that this lake exists, sending a radar signal to the surface and subsurface, and examining what bounces back. (In the above photo, the blue indicates the presence of the lake.) However, this is not definitive proof. NASA hopes to obtain more evidence when their InSight Lander lands in November to make geologic observations. It's possible microbial life survives, or lived at point over the last three billion years. On Earth, microbes have been discovered living in sub-glacial lakes in Antartica and the Arctic.

"We have long since known that the surface of Mars is inhospitable to life as we know it," Dr. Manish Patel from the Open University told BBC News, "so the search for life on Mars is now in the subsurface. This is where we get sufficient protection from harmful radiation, and the pressure and temperature rise to more favourable levels. Most importantly, this allows liquid water, essential for life."

radar discovers lake on Mars Credit: USGS Astrogeology Science Center, ASU

Potentially, scientists could fly a robot to Mars and drill through 1.5 kilometers (0.93 miles) of ice into the water-pocket. Other researchers have successfully done so in Antarctica. However, such a mission would be ambitious. The drilling apparatus would need to be formidable, and the technology is not available right now.

The discovery of this lake is exciting, but don't expect to make a Martian pen pal yet. "We are not closer to actually detecting life," Dr Patel told BBC News, "but what this finding does is give us the location of where to look on Mars. It is like a treasure map - except in this case, there will be lots of 'X's marking the spots."

If you'd like to get a better look at Mars without traveling to that hostile landscape, mark your calendars: Between July 27 and July 30, the Red Planet is coming closer to Earth than it's been in 15 years.