The James Webb Telescope has discovered the chemical composition of an exoplanet’s atmosphere

The James Webb Telescope takes home another record. He managed to provide a molecular and chemical portrait of the skies above the exoplanet Wasp-39 b , which orbits a star 700 light-years away from us, and he managed to do it like never before. In fact, unlike other telescopes, such as Hubble and Spitzer, which have managed to detect single ingredients of the atmosphere of this exoplanet, the James Webb , thanks to its super sensitive instruments, has managed to identify with unprecedented precision atoms, molecules , signs of active chemistry and many other elements, including water, sulfur dioxide, carbon monoxide, sodium and potassium .
By identifying the details of an exoplanet ‘s atmosphere , the Webb telescope ‘s instruments performed well beyond scientists’ expectations and promise a new phase of exploration. “We will be able to see the big picture of exoplanet atmospheres ,” said Laura Flagg , a researcher at Cornell University and a member of the international team that reviewed the new data. “It’s incredibly exciting to know that everything will be rewritten. That’s one of the best parts of being a scientist.”
The results of this comprehensive menu of Wasp-39b atmospheric ingredients are collected in five scientific papers (3 in press and 2 under review). “We observed the exoplanet with several instruments that together cover a large portion of the infrared spectrum and a variety of chemical fingerprints that had been inaccessible until today ,” said Natalie Batalha , an astronomer at the University of California, Santa Cruz. who contributed and helped coordinate the new research. “Data like this is a game changer.”
Among the new information provided by the James Webb Telescope is the first detection in an exoplanet’s atmosphere of sulfur dioxide , a molecule produced by chemical reactions triggered by high-energy light from the planet’s parent star. On Earth, the European Space Agency (ESA) reminds us , the protective ozone layer in the upper atmosphere is created in a similar way. “This is the first time we’ve seen solid evidence of photochemistry on exoplanets,” Shang-Min Tsai explained., researcher at the University of Oxford and lead author of the article which, in fact, explains the origin of sulfur dioxide in the atmosphere of Wasp-39 b. Other atmospheric constituents detected by the Webb telescope are: sodium, potassium, water vapor, carbon dioxide at a higher resolution (providing double the data reported by previous observations), and carbon monoxide (CO). However, he reported no obvious signs of either methane or hydrogen sulfide, probably because their concentrations are very low.
Having such a detailed list of the chemical ingredients of an exoplanet’s atmosphere will give scientists a glimpse of the abundance of the different elements present but also a unique opportunity to observe and study how they relate to each other. This information can help us understand how this exoplanet (and perhaps others) was formed. “The abundance of sulfur relative to hydrogen suggests that the planet has presumably experienced a significant accretion of planetesimals capable of supplying these ingredients to the atmosphere ,” said Kazumasa Ohno , a research scientist at UC Santa Cruz.“The data also indicate that oxygen is much more abundant than carbon in the atmosphere. This potentially means that Wasp-39b originally formed far from the central star.”