Tecnologia

NASA finds more evidence that Mars could have once supported life

Junho 08, 2018 07:20·
What has Nasa found on Mars? Alien life? Watch announcement livestream here

What has Nasa found on Mars? Alien life? Watch announcement livestream here

Organic molecules are the building blocks of life, though they can also be produced by chemical reactions unrelated to life.

No matter its goal, these work as "chemical clues" for researchers about Mars.

In the end, a few smidgens of organics remained, including benzene and propane molecules. And if life does exist elsewhere, it may be very different or even form differently from how we understand life on Earth.

These are exciting findings, published as twin papers in the journal Science today (June 7).

Questions remain, however, as to how the organic material was formed. "While we don't know the source of the material, the wonderful consistency of the results makes me think we have a slam-dunk signal for organics on Mars", Eigenbrode said.

"What this new study is showing in some detail is the discovery of complex and diverse organic compounds in the sediments".

The Curiosity rover landed on Mars in 2012 with a detective's mission: to find clues about whether or not life could exist on the Red Planet.

Regardless, the detection is a technical achievement, said Williford, because it demonstrates that organic molecules can persist near Mars's surface for billions of years.

And although hopes were high that the two landers and their instruments would detect signs of life or organic compounds in samples taken from the surface, that didn't happen. After carefully accounting for background contamination from SAM, Freissinet and her colleagues baked 3-billion-year-old mudstone samples at over 500 degrees C, a temperature at which perchlorates should have fully burned away. It likely held a lake, and now includes a mountain. Mars2020 will shed light on the organic molecules-and prepare a sample that some future mission could bring back to Earth. If scientists keep drilling deeper and more widely, as they plan to do with the European and Russian space agencies' ExoMars rover and NASA's Mars 2020 mission, who knows what they might find?

Potential contaminants were analyzed and accounted for, so the results are the most conclusive yet. Then the scientists sifted through the results to figure out what might be genuine Martian organics.

"This is a significant breakthrough because it means there are organic materials preserved in some of the harshest environments on Mars", said lead author of one of two studies in Science, Jennifer Eigenbrode.

Researchers had previously revealed the discovery of methane in the Martian atmosphere, and this latest discovery builds upon that via season-based variations. With five years of data from a single location, they now have answers.

The methane is cool, whether it's linked to life or not. But the origin of methane on Mars has always been debated.

There's enough ambient carbon and hydrogen in the solar system that they react to form basic organic compounds pretty frequently, even without biology involved, ten Kate said. The release of methane is an active process on Mars, which could suggest new things about what's unfolding on the Red Planet.

While these findings are not necessarily evidence of life on Mars, it is a "good sign for future missions exploring the planet's surface and subsurface", according to NASA.

"People have been wondering about whether there might be life on Mars forever and finally ... they've done all the tests they've modified everything to be able to show that in fact there's organic matter on Mars".

Launched in 2011, Curiosity was created to assess whether Mars ever had an environment able to support small life forms called microbes. I want to know their story.

Notícias recomendadas

Junte-se à conversa

We are pleased to provide this opportunity to share information, experiences and observations about what's in the news.
Some of the comments may be reprinted elsewhere in the site or in the newspaper.
Thank you for taking the time to offer your thoughts.