Scientists Discover Potential Atmosphere On Molten Rocky Exoplanet TOI-561 B

NASA astronomers have potentially identified an atmosphere on a distant exoplanet. The James Webb Space Telescope provided evidence suggesting that TOI-561 b, also known as Super-Earth, might possess an atmosphere. This rocky planet, located beyond our solar system, is extremely hot and covered in lava with magma oceans. Despite its size being 1.4 times that of Earth, it was previously thought too small and hot to maintain an atmosphere.

Recent observations indicate that TOI-561 b might have a persistent atmospheric layer. This finding could challenge previous assumptions about planets with extreme conditions. Nicole Wallack, a Carnegie Science Postdoctoral Fellow and co-author of the study published in The Astrophysical Journal Letters, stated that the planet is enveloped by a "thick blanket of gas." This contradicts the traditional understanding of ultra-short-period planets.

Johanna Teske, lead author and staff scientist at Carnegie Science Earth and Planets Laboratory, noted the planet's unusually low density. She explained that while it isn't classified as a super-puff, its density is lower than expected for a planet with an Earth-like composition. The research team speculates this low density may result from a small iron core and less dense rocky mantle compared to Earth's.

TOI-561 b stands out among ultra-short period planets due to its orbit around an ancient star—twice as old as our Sun—in the Milky Way's thick disk region. Teske highlighted that this suggests the planet formed in a chemically distinct environment from those in our solar system. Although small, the planet appears larger from afar, possibly due to its thick atmosphere.

The research team used Webb's NIRSpec (Near-Infrared Spectrograph) instrument to measure the planet's daytime temperature. They achieved this by observing the decrease in brightness when TOI-561 b passes behind its star.

This discovery opens new avenues for understanding extreme exoplanets and their atmospheres. It challenges existing theories about planetary formation and composition in diverse environments across the galaxy.

With inputs from WAM