Imagine a planet 120 light-years away showing signs of life… or something close to it. Meet K2-18b, a distant exoplanet orbiting a cool red dwarf in the constellation Leo. It's about 8.6 times the mass of Earth and might belong to a strange new class of planets called “sub-Neptunes” - with thick hydrogen-rich atmospheres possibly floating above vast oceans.

When scientists recently aimed the James Webb Space Telescope at K2-18b, what they saw was jaw-dropping. During the planet's transit across its star, they detected methane and carbon dioxide - key molecules that often hint at biological activity. Even more intriguing? A possible whiff of dimethyl sulfide (DMS), a molecule on Earth mostly produced by marine microbes.

But before you scream “aliens!” - scientists are urging caution.

The DMS signal is faint and not yet verified. Plus, it isn't exclusive to life. Even comets in our solar system carry it without any biology involved. And then there's the planet itself: we still don't fully understand its temperature, surface, or internal conditions. It could be a life-friendly ocean world… or an uninhabitable pressure cooker.

Still, the discovery is monumental. It shows how far astronomy has come - from spotting planets to analyzing their chemical fingerprints across the galaxy.

While K2-18b may not hold life, it might just be the beginning of a new era in space science - where the question shifts from “Are we alone?” to “Where should we look next?”