Webb Telescope Reveals Super-Earth Looks Like Mercury

Scientists just took the first detailed look at the bare surface of a rocky planet beyond our solar system, and what they found is changing how we study distant worlds.

Using the James Webb Space Telescope, researchers examined LHS 3844 b, a planet sitting just 48.5 light years from Earth. Instead of just studying its atmosphere like usual, they actually analyzed the rock and dust covering its surface.

The planet turned out to be a hot, airless world covered in dark basalt rock, similar to volcanic material found on Earth or the Moon. It's about 30% larger than Earth but couldn't be more different in character.

LHS 3844 b orbits so close to its star that one year there lasts just 11 hours. One side constantly faces the star, baking at temperatures around 1,340 degrees Fahrenheit, while the other remains in permanent darkness.

The breakthrough came from Webb's ability to detect infrared light coming directly from the planet's surface. Scientists compared this light signature to rocks and minerals from Earth, the Moon, and Mars to figure out what the planet is made of.

They ruled out granite-like materials similar to Earth's crust, which typically form through plate tectonics and often require water. Instead, the surface appears to be iron-rich basalt or weathered regolith, darkened over time by radiation and meteorite impacts.

Why This Inspires

This discovery represents something entirely new in space exploration. For the first time, scientists can study the actual geology of planets orbiting other stars, not just their atmospheres or temperatures.

Former PhD student Sebastian Zieba, who led the research team, explained that the planet likely contains little water and doesn't experience Earth-like plate tectonics. These findings give scientists crucial clues about how rocky planets form and evolve under extreme conditions.

The research also showcases what the James Webb Space Telescope was built to do. Its sensitivity allows astronomers to detect faint light from a small planet's surface, even when that planet sits nearly 50 light years away and can't be directly photographed.

Director Laura Kreidberg summarized the achievement simply: "We see a dark, hot, barren rock, devoid of any atmosphere." While that might not sound uplifting, it represents a milestone in our ability to understand the universe.

Scientists now have a proven method for studying the surfaces of distant rocky planets, opening up an entirely new field of research beyond our solar system.