The blasts of ultraviolet and X-ray radiation can rip away a nearby exoplanet's atmosphere and limit the possibility for alien life.
Hold up - temperate planet? Close inspection reveals that Ross 128 has a odd multiple appearance as this image was created from photographs taken over a more than forty year period by the Digitized Sky Survey 2, and the star, which is only 11 light-years from Earth, moved across the sky significantly during this time.
The closest one, known as Proxima b, may be less hospitable for life.
The Earth-sized planet, named Ross 128b, is just 11 light years away and thought to have a relatively mild climate with temperatures ranging between an icy -60°C and balmy 20°C.
It is also the closest planet to be discovered orbiting an inactive red dwarf star, which may increase the likelihood that this planet could potentially sustain life.
"Those flares can sterilize the atmosphere of the planet", said Xavier Bonfils of the Institute of Planetology and Astrophysics in Grenoble, France, lead author of a paper describing the planet. Dubbed Ross 128 b, the newfound world is about 11 light-years from our solar system, in the constellation Virgo.
The "tug-of-war" between star and planet is revealed in shifts in the wavelengths of light emitted by the star. "Even better, the planet may orbit in the inner edge of its red star's habitable zone, where there could be water". Ross 128 b is 20 times closer to its star than Earth, taking a mere 9.9 days to complete one orbit.
Conditions on the closest exoplanet to Earth that sits in a habitable zone, Proxima Centauri b, are likely to be far less pleasant. NASA explains that while Ross 128 b and Proxima b are in the habitable zone and seem similar to Earth, Venus and Mars would feature numerous same qualities from 11 light years away. Also a red dwarf, it's considered an active star, meaning it frequently burps out intense, high-energy solar flares. Follow-up observations are needed to determine whether Ross 128 b orbits within or near the habitable zone where liquid water could exist on the planet's surface.
Although it is now 11 light-years from Earth, Ross 128 is moving towards us and is expected to become our nearest stellar neighbor in just 79,000 years. It's actually easier to detect exoplanets around red dwarfs because the stars are much fainter (none are visible with the naked eye from Earth) and thus don't wash out their surroundings as drastically.
"Ten years from now, we will be capable, thanks to giant telescopes, to directly "see" the planet and characterize its atmosphere", Astudillo-Defru told Futurism via email. Ross 128 appears at the center of the picture. Bonfils says it's possible that clouds accumulate on the side of the planet facing the star, which could reflect a lot of the star's radiation out into space.
Kenneth Chang is a New York Times writer.