Astronomers get clearest look yet at exoplanet LHS 3844 b's barren surface
Updated
Updated · Reuters · May 7
Astronomers get clearest look yet at exoplanet LHS 3844 b's barren surface
9 articles · Updated · Reuters · May 7
Using NASA's James Webb Space Telescope, researchers found the rocky world 49 light-years away is airless, lifeless and likely basalt-rich, resembling Mercury.
The planet, 30% larger than Earth, orbits a red dwarf every 11 hours and is tidally locked, with a 1,340F dayside and no detectable heat on its nightside.
The Nature Astronomy study builds on earlier JWST findings of a dark, olivine-rich terrain and shows the telescope can directly probe rocky exoplanet geology, not just atmospheres.
Why did one super-Earth become a barren rock while another became a volcanic world with an atmosphere?
With JWST revealing a barren super-Earth, are truly habitable Earth-like planets rarer than we ever imagined?
Now that we can analyze an exoplanet's minerals, can JWST actually map the terrain of these distant worlds?
James Webb Space Telescope Detects Geologically Dead, Airless Surface on Super-Earth LHS 3844 b
Overview
In 2023 and 2024, the James Webb Space Telescope used its MIRI instrument and advanced data processing to observe secondary eclipses of the super-Earth LHS 3844 b, detecting its infrared glow and generating a detailed emission spectrum. Analysis revealed the planet has no atmosphere and a surface made of dark volcanic basalt, unlike Earth's granite-rich crust. The lack of volcanic gases indicates no current geological activity, making LHS 3844 b a geologically dead, airless world. Tidally locked and exposed to intense stellar radiation, its surface is ancient and heavily weathered, resembling Mercury or the Moon. This discovery challenges assumptions about rocky exoplanets around red dwarfs and guides future searches for habitable worlds.