A paper from the Massachusetts Institute of Technology (MIT) suggests life could exist outside Earth’s nitrogen- and oxygen-rich atmosphere.
The study prompts scientists to “imagine if, in our search, we did encounter alien organisms but failed to recognize them as actual life.”
Newly published research from MIT encourages astronomers to search hydrogen-rich planets outside our solar system for signs of life.
The study, published in the journal Nature Astronomy, aims to cast “a wider net for what kinds of environments beyond our own might actually be habitable.” It also proposes a move beyond a “terra-centric” view of life.
Led by Sara Seager, astrophysicist and planetary scientist at MIT, scientists conducted experiments with microbes of yeast and E.Coli, a type of bacteria that normally lives in the intestines.
When placed in an atmsophere comprised entirely of hydrogen, the microbes miraculously survived. In comparison, hydrogen is present in the Earth’s atmosphere in less than one part per million.
These results prompt researchers to study exoplanets – also known as planets outside our solar system. Seager explains that life forms on exoplanets might be easier to spot, because hydrogen-heavy atmospheres typically extend far from their planet’s surface.
“There’s a diversity of habitable worlds out there, and we have confirmed that Earth-based life can survive in hydrogen-rich atmospheres,” Seager says. “We should definitely add those kinds of planets to the menu of options when thinking of life on other worlds.”
If scientists ever sample a hydrogen-rich exoplanet, Seager imagines it won’t look vastly different from Earth. The astrophysicist visualizes hydrogen-dense minerals and oceans, as all life needs liquid to survive.
“You could probably still see a blue sky,” Seager says. “We haven’t thought about the entire ecosystem. But it doesn’t necessarily have to be a different world.”