Proxima b unlikely to be habitable

WASHINGTON: Dampening hopes of finding alien life on the closest exoplanet ever discovered, a new Nasa study says that the atmosphere of Proxima b — an Earth-sized planet right outside our solar system in the habitable zone of its star — might have been destroyed by harmful stellar radiation, reducing its potential for habitability.
At only four light-years away, Proxima b is our closest known extra-solar neighbour. However, due to the fact that it has not been seen crossing in front of its host star, the exoplanet eludes the usual method for learning about its atmosphere.
Instead, scientists must rely on models to understand whether the exoplanet is habitable.
One such computer model considered what would happen if Earth orbited Proxima Centauri, our nearest stellar neighbour and Proxima b’s host star, at the same orbit as Proxima b.
The Nasa study, published in The Astrophysical Journal Letters, suggests Earth’s atmosphere would not survive in close proximity to the violent red dwarf.
“We decided to take the only habitable planet we know of so far — Earth — and put it where Proxima b is,” said Katherine Garcia-Sage, a space scientist at Nasa’s Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study. — IANS