Red Dwarfs Could Sterilize Alien Worlds of Life 76
astroengine (1577233) writes "Red dwarf stars — the most common stars in the galaxy — bathe planets in their habitable zones with potentially deadly stellar winds, a finding that could have significant impacts on the prevalence of life beyond Earth, new research shows. About 70 percent of stars are red dwarfs, or M-type stars, which are cooler and smaller than the sun. Any red dwarf planets suitable for liquid water, therefore, would have to orbit much closer to their parent star than Earth circles the sun. That presents a problem for life — at least life as we know it on Earth, says physicist Ofer Cohen, with the Harvard-Smithsonian Center for Astrophysics. Cohen and colleagues used a computer model based on data from the sun's solar wind — a continuous stream of charged particles that permeates and defines the solar system –- to estimate the space environment around red dwarf stars. 'We find that the conditions are very extreme. If you move planets very close to the star, the force of this flow is very, very strong. Essentially it can strip the atmosphere of the planet unless the planet has a strong magnetic field or a thick atmosphere to start with,' Cohen told Discovery News."
Re: What indigenous life exists on red dwarf? (Score:4, Informative)
never heard of it? [wikipedia.org]
Not deadly forever (Score:5, Informative)
See this article [astrobio.net], on the subject, from back in 2009.
. Preliminary results from a dedicated research program have shown that planets around red dwarfs could be habitable if they can maintain a magnetic field for a few billion years ...
... ...
The high-energy radiation is predominantly emitted by young stars. As they age, red dwarfs become less magnetically active, while continuing to shine steadily at visible wavelengths for 100 billion years or more.
Therefore, if an orbiting planet can just hold onto its atmosphere through the wild early years of its red dwarf roommate, it could end up being a decent place to live.