Earth’s deepest living creatures may hold evidence of alien life on Mars

The most suggestive evidence of life so far is Plumes of methane gas in the Martian airany Varies with seasonsOn Earth, methane is often produced by microorganisms—so the gas could be a waste product of underground life. However, Lloyd urges caution. “There are many non-living reasons why methane plumes could be created,” she says.

Moreover, there are many other obstacles that prevent Life in the interior of Mars“Life doesn’t just need water,” Lloyd says. “It needs energy and space, so it needs habitat.” We don’t yet know if the pores in Martian rocks are big enough for microbes. Similarly, Chemical composition of deep rocks This is very important, as it will be a source of chemical energy.

For Magnabosco, the “biggest uncertainty” about life on Mars “is whether it ever arose.” Because we don’t know how the first living things formed from nonliving materials, we don’t know whether conditions on Mars ever arose at all. Suitable for the emergence of life“If life was able to evolve on Mars,” she says, “it has a very good chance of surviving and being on Mars today.”

If this deep biosphere exists on Mars, how would we find it? The obvious idea is to drill into Mars, but we would need to drill 10 kilometers (6.2 miles) or more deep—a tall order even on Earth. Doing that on a planet that lacks breathable air or running water? “It’s much harder,” says Magnabosco.

More like this:
• Deepest hole ever drilled
• Could we have brought life to Mars?
• How the search for alien life is increasing

However, it should be possible to build supporting evidence. Sample return from Mars The mission will return Martian rocks to Earth: These samples may contain traces of life..

“Chasing the methane would be really useful,” Lloyd says. “Right now, we don’t know where the gas is coming from. If we find pockets of water associated with the methane plumes,” This would be a suggestion. Of life, you say.

Finally, if Mars does indeed have water moving around, we could take advantage of that. On Earth, features like hot springs bring water From the depths of the earth to the surface“There are mud volcanoes on Mars,” Lloyd says. “There are places on Mars where you can go where you can find samples deep beneath the surface that have been extracted and brought to the surface.”

It could be decades before we have a definitive answer. And that answer could be frustrating: Mars is less tectonically and hydrologically active than Earth, suggesting that life is either rare or nonexistent. “We might be looking for life that hasn’t been around for a long time,” Lloyd says. In that case, we might find only fossil evidence, not living organisms. “Either way, it’s life on Mars,” she says.

Michael Marshall is a freelance science and environmental journalist and author of Journey of Genesis: Geniuses and Strangers on a Journey to Discover the Origin of Life on Earth.

—

If you like this story, Subscribe to the newsletter for the main list – A hand-picked selection of can’t-miss features, videos and news, delivered to your inbox twice a week.