How the Evidence for Alien Life on K2-18 b Evaporated

It feels like every time we publish an article about an exciting discovery of a potential biosignature on a new exoplanet, we have to publish a follow-up one a few months later debunking the original claims. That is exactly how science is supposed to work, and part of our job as science journalists is to report on the debunking as well as the original story, even if it might not be as exciting. In this particular case, it seems the discovery of dimethyl sulfide in the atmosphere of exoplanet K2-18 b was a false alarm, according to a new paper available in pre-print form on arXiv by Luis Welbanks of Arizona State University and his co-authors.