Silently floating through the universe are cosmic objects that are both too large to be planets and too small to be stars. Called brown dwarfs, these substellar objects are among the most captivating objects in the universe, and their low surface temperatures mean that most of the light they emit is infrared and thus can only be observed and characterized using infrared telescopes.
Fortunately, the joint NASA/European Space Agency/Canadian Space Agency James Webb Space Telescope is an infrared-sensitive observatory, with the telescope’s powerful suite of instruments primarily observing in the near-infrared and mid-infrared regions of the electromagnetic spectrum. Recently, a team of astronomers used Webb to observe a brown dwarf called W1935 and found an infrared emission from methane in the upper atmosphere of the brown dwarf. While this isn’t an uncommon detection, W1935 does not orbit a star — meaning there isn’t an obvious source behind the emission.