Scientists Now Claim Earth's Closest Exoplanet May Be Able To Sustain Life After All

Thursday, 13 September 2018 - 1:31PM
Science News
Thursday, 13 September 2018 - 1:31PM
Scientists Now Claim Earth's Closest Exoplanet May Be Able To Sustain Life After All
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Image Credit: Pixabay Composite

Could we be one step closer to finally putting this cursed rock we call Earth in our rearview forever and moving on to a new world? While that may thinking a little too far ahead, new research published in the journal Astrobiology suggests that the exoplanet closest to us –Proxima Centauri b – may have what it takes to sustain life.

The team of researchers used computer model simulations to study a range of climate scenarios on Proxima Centauri b, a planet 1.3 times the mass of Earth that orbits a red dwarf star just over 4 light years away from our sun. Operating under the assumption that Proxima Centauri b has an ocean and an atmosphere, they were able to create and run 18 simulations that considered variables like continent sizes, thinner/thicker atmospheres, and ocean salt content, all to determine how living organisms on the planet would fare in the different scenarios. "The major message from our simulations is that there's a decent chance that the planet would be habitable," NASA Goddard Institute scientist and lead author Anthony Del Genio told LiveScience. Proxima Centauri b is in its host star's habitable zone, but one part of the planet experiences eternal darkness because it never faces the star. However, according to the new simulations, heat may be transferred to that part of the planet by a circulating ocean, which would presumably keep it from being a dead frozen wasteland.

In the study's abstract, the researchers note that "an ocean-covered Proxima b could have a much broader area of surface liquid water but at much colder temperatures than previously suggested, due to ocean heat transport and/or depression of the freezing point by salinity. Elevated greenhouse gas concentrations do not necessarily produce more open ocean because of dynamical regime transitions between a state with an equatorial Rossby–Kelvin wave pattern and a state with a day–night circulation."

Opening quote
"For an evolutionary path leading to a highly saline ocean, Proxima b could be an inhabited, mostly open ocean planet with halophilic life."
Closing quote



"Even though the night side never sees any starlight, there's a band of liquid water that's sustained around the equatorial region," Del Genio told LiveScience. He added that "the larger the fraction of the planet with liquid water, the better the odds that if there's life there, we can find evidence of that life with future telescopes." There is no real consensus yet when it comes to PCb's habitability, and with each new study things seem to get more complicated. Solar winds may be a threat to life there and solar flares may have scorched everything just last year. Either way, we're not getting our hopes up because any plans to colonize the planet likely won't happen in this lifetime.

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