In 2011, a group of scientists discovered the exoplanet WASP-39b. A gas giant with a mass level similar to that of Saturn, but with a size closer to that of Jupiter. The giant orbits around its star at a distance equivalent to the one that Mercury orbits from our Sun. For this reason, you can expect a very hot surface, and according to recent measurements by James Webb, it is also very toxic.
Thanks to the James Webb instruments, scientists have been able to find out what are the chemical elements that make up the atmosphere of WASP-39b. The result is a list of gases, each more toxic than the last.. Although it has never been directly observed due to its distance of 700 light years from Earth, at least we can already imagine what its surface looks like.
It is not the first time that James Webb has examined an exoplanet. Earlier this year, shortly after the space telescope’s activation, he observed WASP-96b’s atmosphere. At that moment, a large amount of vapor was revealed in its atmosphere; something that greatly surprised scientists since, at the time of its discovery, this exoplanet had been cataloged as the first without clouds.
The James Webb reveals the dangerous atmosphere of WASP-39b
Among the new molecules and chemicals found on the surface of WASP-39b, we have evidence of water, carbon monoxide, sodium, potassium, and sulfur dioxide.
That the James Webb was able to detect these tracks at such a far distance is an achievement in itself. To make it, the telescope watched the planet carefully until it passed in front of its star. When he did, the planet was backlit, allowing scientists to deduce the chemicals in the atmosphere from the light waves they absorbed.
It is an intelligent and quite effective method of capturing information from distant bodies. The only problem is that they are almost always confined to gas giant planets that are very close to their star; since in case of emitting a very small shadow, it would be very difficult to capture the information thrown by the exoplanet.
“It’s the first time that concrete evidence of photochemistry is observed -chemical reactions initiated by energetic starlight- on exoplanets,” says Shang-Min Tsai, a researcher at the University of Oxford and lead author on the study demonstrating the presence of sulfur dioxide in the planet’s atmosphere.
A hope for the search for habitable planets in the future
This detection tool through photochemistry is something that raises great hopes among scientists. Specifically because of the ability that exists with the James Webb of search for planets with ideal conditions for life. Sure, with WASP-39b we’re not going anywhere, but in the future we could study smaller, rocky planets that may have a similar composition to our Earth.
“I’m looking forward to seeing what we find in the atmospheres of small terrestrial planets,” comments Mercedes López-Morales, astronomer at the Center for Astrophysicists | Harvard & Smithsonian, and co-founder of the study.
A few months ago, James Webb captured its first image of an exoplanet. It would be located about 385 light-years away, closer than WASP-39b, and also aims to be a gas giant.