NASA Says the Alpha Centauri Star System May Support Life—And It's Right Next Door to Us
Ever since astronomers realized that the closest Earth-like exoplanet, Proxima b, is probably an irradiated hellscape, excitement over the prospect of visiting the nearby Alpha Centauri system has waned.
Though it's only four light-years away (the closest of any star system), what's the point of visiting Alpha Centauri's three stars if there will be nothing there to greet us but dead worlds?
Well, new research from NASA's Chandra X-Ray Observatory has proven that at least two of Alpha Centauri's stars, designated Alpha Centauri A and B, actually could allow life to develop on nearby planets.
The new study draws on 13 years worth of data and builds on previous research published in Research Notes of the American Astronomical Society. It points out that Alpha Centauri A's radiation output is less than our own Sun's, and B's radiation is only slightly higher.
According to Tom Ayres, a Senior Research Associate at the University of Colorado, says Alpha Centauri B's radiation levels aren't too concerning:
"It's probably okay, it's not crazy higher than the sun. Chandra shows us that life should have a fighting chance on planets around either of these stars."
No planets have been found orbiting either of these milder stars yet, but astronomers are still looking.
"The Alpha Centuari system will be the first stop for interstellar travelers from Earth," says Ayers. "The age of the system is similar to the sun, which is good for the development of life."
Right now, the process of determining whether a planet is a good candidate for life is still roller coaster ride.
The Trappist-1 system, for example, seemed like an ideal candidate—its planets were small and rocky, their orbits kept them at a good distance from their star, and they had an excellent chance of having liquid water on their surfaces.
Then, in a strange twist of fate, it turned out that those planets may have too much liquid water to create the chemical reactions necessary for life.
Meanwhile, Michio Kaku has suggested that icy ocean worlds, not temperature ones, may be one of the more likely places to find intelligent life. Only time (and more powerful telescopes) will tell.