Scientists have just made a huge breakthrough in the search for alien life.
A gas “uniquely associated with life” has possibly been discovered on the massive K2-18b exoplanet.
NASA’s James Webb Space Telescope has been probing the planet, which lies in the labelled habitable zone, 120 light-years from Earth.
The K2-18b exoplanet, in the constellation Leo, doesn’t have any other planets nearby and is poorly understood.
However, it’s now been revealed to have carbon-bearing molecules.
These include methane and carbon dioxide, as well as possibly dimethyl sulfide (DMS), which on Earth is only produced by life, according to NASA.
“Even the prospect of it is mind-boggling,” said the studies’ lead author.
The discovery comes off the back of recent studies that suggest K2-18b could possess a hydrogen-rich atmosphere and a water ocean, making it a promising location in the search for alien life.
But, the discovery of DMS pushes the planet to the top of the list.
“Upcoming Webb observations should be able to confirm if DMS is indeed present in the atmosphere of K2-18b at significant levels,” said Nikku Madhusudhan, an astromer at the University of Cambridge and lead author of the paper announcing these results.
“Our ultimate goal is the identification of life on a habitable exoplanet, which would transform our understanding of our place in the universe.
“Our findings are a promising step towards a deeper understanding of Hycean worlds in this quest.”
Just because K2-18b lies in the habitable zone and is now known to barbour carbon-bearing molecules, doesn’t necessarily mean the planet can support life.
For starters, the planet’s large size means that its exterior likely contains a “large mantle of high-pressure ice”.
In other words, it’s similar to Neptune, but with a thinner hydrogen-rich atmosphere and an ocean surface.
“The abundance of methane and carbon dioxide, and shortage of ammonia, support the hypothesis that there may be a water ocean underneath a hydrogen-rich atmosphere in K2-18b,” NASA stated.