NASA’s James Webb Space Telescope might have discovered potential proof of life in the atmosphere of a planet located about 744 trillion miles from Earth.
An international team of astronomers, led by Cambridge University professor Nikku Madhusudhan, announced their findings Sept. 11, and the results were accepted for publication in The Astrophysical Journal Letters.
Using the data from the new telescope, the experts found methane and carbon dioxide in the atmosphere of K2-18b, an exoplanet in the “Goldilocks region” — a habitable zone where planets orbit at the “just right” distance from a star known as K2-18, that is not too hot or too cold to host liquid water, and therefore could potentially support life.
K12-18 is a K-type red dwarf star that’s located about 110 light-years from Earth in the constellation Leo. K stars are dimmer than the Sun but brighter than the faintest stars, according to NASA.
Red dwarf stars are too dim to see with the naked eye and make up the galaxy’s largest population of stars, according to Space.com. Their dimness helps prolong their lifespans, which are greater than the Sun’s.
The exoplanet, K2-18B, is 8.6 times as large as Earth, yet smaller than Neptune, classifying it as a “sub-Neptune” planet — some of the most common types of exoplanets.
The news has excited astronomers and pundits on social media, with one British science reporter exclaiming: “This is pretty huge. If confirmed, it’d be the biggest hint of alien life discovered so far.”
“Important in seeking extraterrestrial life is to ‘follow the water.’ The more exoplanets we find in habitable zones, the greater the chance that they’ll be able to support some form of life, and eventually, we’ll detect the signature of such life,” another wrote.
“We need to keep looking through using serious scientific processes,” the same person added. “At some point, perhaps years or decades hence, and with enough time and with investment in the right technology, we’ll find the evidence that answers the most basic scientific question facing humanity – ‘are we alone?’
However, the surface of K12-18b appears to consist mostly — or entirely — of liquid water, which would make the world a hycean, a portmanteau of “hydrogen” and “ocean.”
While its atmosphere consists of mainly hydrogen and small amounts of methane and carbon dioxide were found, the data also discovered that there are possibly trace amounts of dimethyl sulfide (DMS).
DMS is considered to be a biomarker — evidence of life — and is found on Earth only as an artifact of microbial metabolism. However, the data for DMS on K12-18b is not yet conclusive.
The current signs of DMS are unconfirmed and require further confirmation, researchers believe that K12-18b could be the greatest chance of discovering life outside of our Solar System.