TechWebb Telescope discovers water vapor on a nearby planet

Webb Telescope discovers water vapor on a nearby planet

James Webb Space Telescope
James Webb Space Telescope
Images source: © NASA
7:52 AM EST, November 17, 2023

The James Webb Space Telescope has detected water vapor in the atmosphere of a nearby planet, WASP-107b. This is noteworthy, scientists point out, as it could contribute significantly to planetary research, particularly in understanding the relationship between a planet's chemical composition and its climate.

With the help of the James Webb Space Telescope, researchers discovered water vapor, sulfur dioxide, and silicon dioxide clouds, the main constituent of ordinary sand, in the atmosphere of the exoplanet WASP-107b. This planet is relatively close to Earth, about 200 light-years away. This discovery marks a significant milestone in planetary research, notably correlating chemical composition with climate dynamics.

The discovery was reported by scientists from the Catholic University in Leuven (KU Leuven) and other European research institutions. An article detailing the findings has been published in the prestigious "Nature" journal.

A first for the James Webb Space Telescope

The state-of-the-art James Webb Space Telescope enabled scientists to thoroughly analyze the atmosphere of the exoplanet WASP-107b. This planet orbits a star slightly cooler and less massive than our Sun. Intriguingly, while it has a mass similar to Neptune, its size approaches that of Jupiter.

Scientists note that the planet's "fluffiness" permitted a 50-times deeper exploration of its atmosphere than that of our solar system’s gas giants, like Jupiter. Notably, methane was absent in the atmosphere of WASP-107b, implying that the planet's interior is warm. The detection of sulfur dioxide was an unexpected discovery.

In past models, there was an assumption of no sulfur dioxide on the planet. However, new climate simulations for WASP-107b suggest that the planet's "fluffiness" promotes the right conditions for the formation of this particular compound. This can be attributed to the planet's thin atmosphere, which allows the parent star's radiation to penetrate deeply and trigger the necessary chemical reactions.

Furthermore, scientists observed that the radiation emitted by sulfur dioxide and water vapor is considerably weaker than would be possible if clouds were absent. Analysis of WASP-107b's atmosphere revealed clouds composed of silicon dioxide, the primary component of common sand.

"The JWST revolutionizes exoplanet research by providing unprecedented insight at an incredible pace," says team leader Leen Decin. "The discovery of sand, water, and sulfur dioxide clouds on this fluffy exoplanet by the MIRI instrument on board the JWST is groundbreaking. It reshapes our understanding of planet formation and evolution, casting new light on our own Solar System," she adds.

Scientists explain that these clouds form much like water does on Earth; silica vaporizes and condenses under high-temperature conditions. However, the prevalent temperature of 932 degrees Fahrenheit in the layers of WASP-107b's atmosphere being studied is too low for such clouds to form.

"The fact that we observe these sand clouds high in the atmosphere suggests that droplets of sand rain evaporate in deeper, hotter layers, and the resulting silica vapors are effectively transported upwards, where they re-condense into clouds. This mirrors the water vapor and cloud cycle on Earth, only with sand droplets," explains co-discoverer Dr. Michiel Min.

Scientists conclude that this consistent cycle of sublimation and condensation accounts for the persistent presence of sandy clouds in the atmosphere of WASP-107b.

Related content