Why some scientists believe life may have started on Mars

On February 18, NASA’s Perseverance rover will parachute through thin Martian air, marking a new era in red planet exploration. Landing on the Jezero Crater, which is located north of the Martian equator, will be no easy feat. Only about 40 percent of the missions ever sent to Mars succeed, according to NASA. If it does, Perseverance could drastically change the way we think about extraterrestrial life. That’s because scientists believe Jezero, a 28 mile-wide impact crater that used to be a lake, is an ideal place to look for evidence of ancient microbial life on Mars.

Once it lands, Perseverance will collect and store Martian rock and soil samples, which will eventually be returned to Earth. This is known as a “sample-return mission,” an extremely rare type of space exploration mission due to its expense. (Indeed, there has never been a sample return mission from another planet.) And once Martian soil is returned to Earth in a decade, scientists will set about studying the material to figure out if there was ever ancient life on Mars. 

Yet some scientists believe that these samples could answer an even bigger question: Did life on Earth originate on Mars?

Though the idea that life started on Mars before migrating on Earth sounds like some far-fetched sci-fi premise, many renowned scientists take the theory seriously. The general idea of life starting elsewhere in space before migrating here has a name, too: Panspermia. It’s the hypothesis that life exists elsewhere in the universe, and is distributed by asteroids and other space debris.

To be clear, the notion of life on Earth originating on Mars isn’t a dominant theory in the scientific community, but it does appear to be catching on. And scientists like Gary Ruvkun, a professor of genetics at Harvard Medical School, say that it does sound “obvious, in a way.”

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Scientists Believe These Photos Show Mushrooms on Mars—and Proof of Life

Could there be mushrooms on Mars? In a new paper, an international team of scientists from countries including the U.S., France, and China have gathered and compared photographic evidence they claim shows fungus-like objects growing on the Red Planet.

In their paper, which appears in Scientific Research Publishing’s Advances in Microbiologythe scientists analyze images taken by NASA’s Opportunity and Curiosity rovers, plus the Mars Reconnaissance Orbiter’s HiRISE camera. The objects in question show “chalky-white colored spherical shaped specimens,” which the Mars Opportunity team initially said was a mineral called hematite.

Later studies refuted the hematite claim. Soon, some scientists coined the term “Martian mushrooms” to describe the mysterious objects, because of how they resemble lichens and mushrooms, while in another study, fungi and lichen experts classified the spheres as “puffballs”—a white, spherical fungus belonging to the phylum Basidiomycota found on Earth.

In the new paper, the scientists point to a set of Opportunity photos that shows nine spheres increasing in size, and an additional 12 spheres emerging from beneath the soil, over a 3-day sequence. The researchers claim Martian wind didn’t uncover the amorphous spheres, and that they “expand in size, or conversely, change shape, move to new locations, and/or wane in size and nearly disappear.”

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