BULLETIN

First detection of carbon dioxide on exoplanet

The gas could hold key to tracking down life on other planets

Carbon dioxide has been sniffed out for the first time in the atmosphere of a world beyond our Solar System by the James Webb Space Telescope (JWST).

JWST looked at the starlight streaming through the atmosphere of exoplanet WASP- 39b as it passed in front of its star. The telescope was sensitive enough at the right wavelengths that planetary scientists were able to pick out the signatures of water, methane and carbon dioxide.

“Detecting such a clear signal of carbon dioxide on WASP-39b bodes well for the detection of atmospheres on smaller, terrestrial-sized planets,” says research lead Natalie Batalha of the University of California, Santa Cruz. The gas can be used to measure the ratio of solids to gases when the planets formed. Perhaps more critically, it is a gas given off by many organisms on Earth, so could help uncover life on distant worlds. webb.nasa.gov