The James Webb Space Telescope has made what scientists are calling the most compelling detection yet of potential biosignatures in the atmosphere of a distant exoplanet.

K2-18b, a sub-Neptune planet located 120 light-years away in the habitable zone of its star, shows strong spectral signatures of dimethyl sulfide (DMS) and carbon dioxide.

Why DMS Matters

On Earth, DMS is produced primarily by marine phytoplankton. Its detection in an exoplanet atmosphere is not definitive proof of life, but it is widely considered one of the most promising biosignatures.

“The data is consistent with biological activity, but we need to rule out all non-biological sources first,” said Dr. Sarah Kendrew, an astronomer at the Space Telescope Science Institute.

What Comes Next

NASA plans to allocate additional JWST observation time to K2-18b over the next six months. The goal is to gather enough data to confirm or rule out the biological hypothesis.

If confirmed, K2-18b would be the first world beyond our solar system to host known extraterrestrial life.