That’s what a new discovery from a pair of geoscientists at Arizona State University (ASU) could lead to.
To find evidence of life on Mars, scientists often look for similar landscapes on Earth. One of these places is Chile’s Atacama Desert. The extremely dry desert is a great place to throw up telescopes. And it’s also one of the best Mars-like environments on Earth.
ASU’s Steve Ruff and Jack Farmer ventured to a group of hot springs called El Tatio at the edge of the Atacama Desert. Why hot springs? To understand that, we have to go back to 2007.
Nine years ago, NASA’s Spirit rover was cruising around an eroded deposit of volcanic ash called Home Plate inside the Gusev Crater on Mars. What it discovered next happened by accident. The rover’s right front wheel motor gave out. As it continued to move its stuck wheel, it churned through the ground uncovering a rich deposit of pure silica surrounded by outcroppings of the same mineral. Silica is often found in and around hot springs and geysers like Yellowstone, and in this case, El Tatio.
So why not just go to Yellowstone and take a look around? Well, Yellowstone doesn’t exactly look like Mars. But El Tatio is as close as we’re going to find on Earth. Sitting over 14,000 feet above sea level, the active hot springs at El Tatio are some of the highest in the world. This high altitude also means temperatures plunge to below freezing at night. Plus, much more UV light penetrates the thinner air.
If Spirit stumbled upon an ancient Martian hot spring, El Tatio is one of the closest analogs you’re going to find on Earth.
“We went to El Tatio looking for comparisons with the features found by Spirit at Home Plate,” says Ruff. “Our results show the conditions at El Tatio produce silica deposits with characteristics that are among the most Mars-like of any silica deposits on Earth.”
Here’s what NASA’s Spirit saw in 2007.
And this is what Ruff and Farmer saw at El Tatio.
We have no idea how the finger-like Silica deposits formed on Mars, but microorganisms helped shape them at El Tatio.
“The fact that microbes play a role in producing the distinctive silica structures at El Tatio raises the possibility that the Martian silica structures formed in a comparable matter – in other words with the help of organisms that were alive at the time,” adds Ruff.
We have to go back
Slow down Jack. Getting a rover to Mars isn’t easy. Hell, NASA is the only space agency out there who can do it.
There are plans to send a new rover to Mars in 2020, and NASA is still hashing out the landing spot details. Right now, there are eight potential landing sites. The good news for Ruff and Farmer is the Home Plate site in Gusev Crater sits at number 2 on the list. An ancient lakebed in Jezero Crater is the current favorite for NASA’s next Mars rover.
You can make a case for going back to Gusev crater or discovering a new area. Getting a Mars rover to the red planet take a lot of time, and a lot of scientists don’t want to spend it looking at an area they’ve already seen.
But Ruff makes a good case for the flip side. “We know exactly where to land and where to go collect samples. And the silica structures found by Spirit meet the definition of a potential biosignature.”
What we need are more rovers. It’s a damn shame NASA doesn’t get more funding. Half a percent of the Federal Budget? That’s a joke. During the space race in the 1960s, it was between 2-4%. Just doubling it to 1% would make a huge difference.
As for the final 2020 rover landing site? Another workshop is set for February 2017 where the 8 spots will be cut to 4. We’ll see if Gusev crater can claw its way to the top by then.
What do you think? Revisit Gusev crater, or cruise towards a new area?