For the First Time, James Webb Space Telescope Detects Semi-Heavy Water in an Exoplanet's Atmosphere

Semi-Heavy Water Detected in the Atmosphere of Exoplanet WASP-39b

According to НВ — Техно: The James Webb Space Telescope has, for the first time, identified semi-heavy water (HDO) in the atmosphere of WASP-39b, a planet located nearly 700 light-years away. This discovery marks a major step in exoplanet research, as the ratio of deuterium to ordinary hydrogen in the planet's water is far higher than what is observed in the Solar System's gas giants. Scientists believe this could result from the loss of lighter water over time or from the planet having formed much farther from its host star before migrating inward.

Studying the Exoplanet's Atmosphere

Using telescope observations, researchers tested various atmospheric models for WASP-39b, taking into account factors such as temperature, cloud cover, and gas composition. This gas giant has a temperature of roughly 1000 °C and orbits its star more than 20 times closer than Earth orbits the Sun. Although WASP-39b is unlikely to support life, its atmosphere may provide crucial clues about the conditions under which planets develop.

To explain the unusually high deuterium-to-hydrogen ratio, the research team proposed two main possibilities:

• Lighter water molecules may gradually escape the atmosphere, while heavier molecules remain longer due to their greater mass.
• WASP-39b may have originated in a colder region of its planetary system, where ice and water were more abundant, and later moved closer to its star.

These findings could have a significant impact on future exoplanet studies, especially efforts to improve methods for finding worlds capable of hosting life.

The detection of semi-heavy water on WASP-39b highlights how modern space observatories are transforming our understanding of alien atmospheres. It also offers new insight into how planetary systems evolve and how water may form on other worlds, which could ultimately guide the search for life beyond our Solar System.

In addition to the significant findings on WASP-39b, the James Webb Space Telescope has also revealed another exoplanet with extreme conditions, showcasing a scorching surface temperature of 126°C. This discovery not only underscores the diversity of exoplanetary environments but also enhances our understanding of atmospheric compositions across different celestial bodies. To learn more about this intriguing exoplanet and its characteristics, check out our detailed report on the scorching surface temperatures.