A surprisingly low reservoir of methane may explain how a planet around a nearby star grew weirdly puffy, according to new observations from the James Webb Space Telescope (JWST). The finding shows that planetary atmospheres can inflate to remarkable amounts without employing esoteric theories of planet formation, astronomers say.
"The Webb data tells us that planets like WASP-107 b didn't have to form in some odd way with a super small core and a huge gassy envelope," Michael Line, an extrasolar planetologist at Arizona State University, said in a statement. "Instead, we can take something more like Neptune, with a lot of rock and not as much gas, just dial up the temperature, and poof it up to look the way it does."
