Astronomers have found that red dwarf stars can produce such high levels of ultraviolet radiation that it could affect the possibility of life on planets close to them. The results of the study have been published in the journal Monthly notices of the Royal Astronomical Society.
Red dwarf stars, which are cooler and smaller than the Sun, make up 75% of the stars in the Milky Way. Some scientists believe that rocky planets orbiting red dwarfs provide suitable conditions for the origin and development of life.
But the authors of a new study have found that red dwarfs can produce intense outbursts with enormous amounts of ultraviolet radiation that are greater than previously thought. The findings could have far-reaching implications for the search for extraterrestrial life on nearby rocky planets.
For their research, the scientists used archived data from the GALEX space telescope, which operated from 2003 to 2013, to look for flares on red dwarf stars within 300 light-years of Earth. As a result, they discovered nearly 200 flashes of both near and far ultraviolet radiation.
Scientists say ultraviolet radiation from stellar outbursts could destroy planets’ atmospheres, compromising their ability to be habitable, or help form the RNA building blocks needed to create life.
The results of the new study challenge existing models of stellar outbursts, as scientists found that far-ultraviolet radiation is on average three times more energetic than expected. Scientists believe that the impact of such radiation on the planet could either destroy its atmosphere or destroy the life that exists there.
According to the authors of the study, it was believed that only a few stars create very strong ultraviolet radiation through outbursts, which can affect the habitability of the planet. But it turned out that a large number of stars have this ability.
So a new study casts doubt on the assumption that rocky planets orbit red dwarfs, where extraterrestrial life could exist. So far, astronomers don’t know why red dwarfs emit so much radiation and this is a topic for future research.
The study’s findings may indicate that most stars in the Milky Way may not have habitable planets. And this could be the answer to the famous Fermi paradox: if aliens exist, where are they all?
