Cambridge scientists detect possible biosignatures on Exoplanet K2-18b
Scientists have detected traces of chemicals in the planet’s atmosphere, which indicate a strong possibility of containing life
Have you ever looked up at the night sky and wondered if something — or someone — is looking back?
A team of researchers at Cambridge University might be edging closer to an answer. Their latest findings suggest that a distant planet, K2-18b, could possibly host life. But the keyword here is possibly.
Orbiting a faint red star 124 light-years from Earth, K2-18b is more than twice our planet's size. Scientists using NASA's James Webb Space Telescope (JWST) have detected traces of dimethyl sulphide (DMS) and dimethyl disulphide (DMDS) in the planet's atmosphere. On Earth, these gases are produced by ocean-dwelling microbes.
Keep updated, follow The Business Standard's Google news channel
"This is the strongest evidence yet that there is possibly life out there," said Professor Nikku Madhusudhan, who leads the Cambridge team.
This is not the first time signs of these gases have been spotted, but the latest readings are far stronger. Still, the team only has a three sigma result — about 99.7% certainty. To confidently declare a discovery, they need five sigma: 99.99999%.
Even with perfect data, scientists like Professor Catherine Heymans of Edinburgh warn that biology is not the only explanation. "We do not know all the ways these gases might form," she said.
Some researchers believe K2-18b may hold a massive ocean. Others suggest it could be a rocky inferno or even a gas giant with no surface at all.
Despite the uncertainty, the Cambridge team is hopeful. "I can realistically say that we can confirm this signal within one to two years," said Prof Madhusudhan. Until then, the mystery remains.
