James Webb Telescope captures clearest-ever view of exoplanet’s surface

Astronomers using NASA’s James Webb Space Telescope have obtained the clearest view yet of the surface of a rocky exoplanet, revealing a scorched, atmosphere-free world that scientists say resembles a giant version of Mercury.

The planet, known as LHS 3844 b and nicknamed “Kua’kua,” appears to be a barren, uninhabitable world with extreme temperature swings and no detectable atmosphere, according to a study published this week in Nature Astronomy.

Researchers said the planet’s surface is likely covered in dark volcanic rock and ancient regolith — loose rocky debris formed over billions of years from relentless bombardment by radiation and micrometeorite impacts.

“This planet is not a nice place,” said astronomer Laura Kreidberg, senior author of the study. “It’s a hellish, barren rock — much more similar to Mercury than Earth.”

Located about 49 light-years away, LHS 3844 b orbits a small red dwarf star and completes a full orbit every 11 hours. The planet is tidally locked, meaning one side permanently faces its star while the other remains in darkness — similar to how the Moon always shows the same face to Earth.

Scientists found the planet’s dayside reaches roughly 1,340 degrees Fahrenheit (725 degrees Celsius), while the nightside showed almost no detectable heat.

Using Webb’s infrared instruments, researchers were able to directly analyze light coming from the planet’s surface — a major breakthrough for exoplanet science.

“Different rocks have different spectral fingerprints,” said lead author Sebastian Zieba. “Dark volcanic rocks like basalt matched our observations much better than brighter rocks like granite.”

The findings mark a new phase in exoplanet research, shifting beyond atmospheric studies toward direct analysis of alien geology and surface composition.

Since becoming operational in 2022, the Webb telescope has transformed scientists’ understanding of planets beyond the solar system, helping identify atmospheric chemistry, weather patterns and now even the nature of distant planetary surfaces.

Researchers said the absence of an atmosphere on LHS 3844 b means there is little protection from stellar radiation and virtually no possibility of liquid water — a key ingredient for life.

“So overall, this is almost certainly not a habitable world,” Zieba said.