Proxima B, one of the exoplanets that was discovered in 2016, located four light-years away from the Earth and was given the name of ‘second Earth,’ gave hopes to scientists that life may be possible on the planet as its position was in the ‘habitable zone’ from its host star. However, this turned out to be a false hope because of the stellar eruptions of the star.
Till now, the condition for life to thrive on a planet was considered to be its position which must be in the habitable zone of its host star. The habitable zone of a star is defined as a safe distance where the planet can allow liquid on its surface. The light and heat of the star must be just right at that distance, and a planet is present in that zone then it is considered livable. But Proxima B, in spite of being in the zone, did not seem to have any trace of life.
Scientists then observed the conditions more deeply, and they found that this zone thing wasn’t just enough as the star continuously emits X-rays, U.V rays along with the stellar eruptions- flares and coronal mass ejections. In the case of Red Stars which were considered best for building life-sustaining environment, the ejection of X-rays and U.V rays was even more.
Vladimir Airapetian, a solar scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland and the lead author of the paper said “If we want to find an exoplanet that can develop and sustain life, we must figure out which stars make the best parents. We’re coming closer to understanding what kind of parent stars we need”.
Proxima B was found to face the torrent rays in about every two hours, concluding that life could never be possible on it.
The findings were published in ‘The Astrophysical Journal Letters.’