An Earth-Like Planet Has Been Discovered To Have An Atmosphere, May Be A Water World

Astronomers continue to find exoplanets, some of which may be water worlds and others which call for a power ranking. Now, for the first time, researchers have found signs of an atmosphere around an Earth-sized planet 39 light years from us. The planet, Gliese 1132b (also known as GJ 1132b), orbits very close to a red dwarf star with one-fourth the Sun’s radius. It orbits so closely that it makes a full orbit every 1.6 days.

GJ 1132b is visible from the southern hemisphere of Earth in the Vela constellation. By studying the planet’s infrared wavelength bands as it transited its star, Dr. John Southworth’s team from Keele University theorized that its atmosphere is made of water or methane or a combination of the two. Southward told BBC, “One possibility is that it is a ‘water world’ with an atmosphere of hot steam.” The planet’s surface may also be rocky and Earth-like, with a ~70% silicate and ~30% iron composition, as the planet’s radius of 1.215 to 1.535 times that of Earth could theoretically allow for either composition and anything in between the two.

Unfortunately, it probably doesn’t contain life, as the surface temperature is 370 degrees Celcius (almost 700 degrees Fahrenheit), and Southwarth said, “To my knowledge the hottest temperature that life has been able to survive on Earth is 120 C and that’s far cooler than this planet.”

The good news is, there are so many small Earth-like planets like this that finding one with an atmosphere bodes well for finding life on other planets. But don’t pack your bags for a trip to GJ 1132b just yet. Based on similar estimates for traveling to a nearby star, getting to an exoplanet 39 light years away would take more than 360,000 years using our current technologies. Oh well; at least we already got to see all those syndicated reruns of The Gong Show GJ 1132b is just now getting.

(Via BBC, the LA Times, and the Astronomical Journal)