Harsh space winds diminish hopes for life on red-dwarf planets

BY Talia Mindich  June 3, 2014 at 4:58 PM EDT
An artist's conception of a planet, with two moons, orbiting a red dwarf star. Image by NASA/Harvard-Smithsonian Center for Astrophysics/D. Aguilar

An artist’s conception of a planet, with two moons, orbiting a red dwarf star. Image by NASA/Harvard-Smithsonian Center for Astrophysics/D. Aguilar

Space winds in the habitable zones of the most common star in the galaxy may be too severe to harbor life, a new study finds.

Due to proximity, stellar winds constantly blowing from red dwarf stars might be so harsh as to strip the atmosphere of any rocky planet orbiting in the star’s habitable zone.

Red dwarf stars are smaller and cooler than the sun, meaning that a planet must be around 9 million to 18 million miles from its host star to be warm enough for liquid water. In contrast, Earth is about 93 million miles away from its sun.

Extreme space conditions may also trigger aurorae — or Northern Lights — 100,000 times stronger than those on Earth.

“If Earth were orbiting a red dwarf, then people in Boston would get to see the Northern Lights every night,” said Ofer Cohen of the Harvard-Smithsonian Center for Astrophysics in a press release.

“On the other hand, we’d also be in constant darkness because of tidal locking, and blasted by hurricane-force winds because of the dayside-nightside temperature contrast,” Cohen added. “I don’t think even hardy New Englanders want to face that kind of weather.”

The research was presented Monday at the American Astronomical Society meeting in Boston.