For decades we could see only stars and a few nearby planets from our own solar system when we looked to the heavens. Twenty years ago we started spotting exoplanets; then potentially habitable exoplanets; and now astronomers have pinpointed the closest exoplanet yet that might support life.
The so-called "super-earth" is one of three planets orbiting a red dwarf star called Wolf 1061 that's just 14 light-years away.
"While a few other planets have been found that orbit stars closer to us than Wolf 1061, those planets are not considered to be remotely habitable," said Duncan Wright, of the University of New South Wales in Australia. Wright is lead author of a study on the discovery that will be published in The Astrophysical Journal Letters.
Wright says it's the middle planet, called Wolf 1061c, that orbits in the habitable "Goldilocks zone" of the star, where temperatures are not too hot and not too cold but just right for liquid water, making life as we know it theoretically possible.
"It is fascinating to look out at the vastness of space and think a star so very close to us -- a near neighbor -- could host a habitable planet," Wright says.
"Near" is of course a very relative term. Current understanding of physical limitations mean it would take at least 14 years to make the journey to Wolf 1061c, and we would have to invent light-speed travel first.
Still, this planet is a much closer neighbor than most other potentially habitable exoplanets spotted so far, which tend to be hundreds or thousands of light-years away. One notable exception is Gliese 667 Cc, which sits 22 light-years away.
If future generations did make it to Wolf 1061c, they'd find an oversize rocky planet circling a star that's dimmer and smaller than our sun.
The UNSW team says it hopes to study the atmosphere of the planet in the future to see if it might be conducive to life. It could also make an excellent candidate for observation by the next generation of powerful telescopes, starting with the Transiting Exoplanet Survey Satellite (TESS) and the James Webb Space Telescope, both set to launch in the next two to three years.
Of course, by that time the math makes it seem likely that we'll have found a number of potentially habitable planets that are even closer still.