A couple of months ago, the results of a study conducted by the James Webb Space Telescope were published, during which methane and carbon dioxide were detected in the atmosphere of one of the exoplanets. It was about K2-18 b, a possible giant planet with a global ocean and a hydrogen-rich atmosphere. Now Webb has discovered methane in the atmosphere of another exoplanet - WASP-80 b. In the spectra obtained using NIRCam, signs of methane and water vapor were detected. And if the researchers found water vapor in at least a dozen extrasolar planets, then methane could not be detected until recently. Recall that methane is a molecule abundantly present in the atmospheres of Jupiter, Saturn, Uranus and Neptune in our Solar System.

Study of WASP-80 b during transit and eclipse, the temperature of WASP-80 b is about 550 degrees Celsius, which puts it in the class of hot Jovian exoplanets close in size and mass to Jupiter. The exoplanet is located 163 light-years away in the constellation of the Eagle. It orbits its host star, a red dwarf, once every three days. Because the planet is so close to its star and both of them are so far away from us, we cannot see it directly even with the most modern telescopes, such as "James Webb". Therefore, researchers study the combined light of a star and a planet using the method of transits and eclipses. Transit occurs when a planet moves in front of its star in an orbit relative to our perspective. At the same time, the light of the star reaching us is somewhat reduced due to the presence of the object. An eclipse occurs when a planet passes behind its star in its orbit relative to our perspective. At the same time, the star's light decreases again due to the absence of light reflected by the planet. During transit, a thin ring of the planet's atmosphere is illuminated by a star. At certain wavelengths, where the molecules of the planet's atmosphere absorb light, the atmosphere appears thicker and blocks more of the star's light. This results in a deeper dimming than at other wavelengths, when the atmosphere appears transparent. This method helps scientists understand what the atmosphere of the planet consists of. However, just before and after the eclipse, infrared radiation emitted by the planet, also known as thermal radiation, can be measured. In the spectra of eclipses, absorption by molecules of the planet's atmosphere usually manifests itself as a decrease in the light emitted by the planet at certain wavelengths.

This result shows that we are on the verge of more and more interesting discoveries. For example, further observations of WASP-80 b using MIRI and NIRCam will allow us to study the properties of the atmosphere in different wavelength ranges of light. And the detection of methane on WASP-80 b suggests that we will be able to observe other carbon-rich molecules, such as monoxide and carbon dioxide. This will allow us to get a more complete picture of the state of the atmosphere of this planet. In addition, having discovered methane and other gases on exoplanets, we will continue to expand our knowledge of how chemistry and physics work in conditions other than those on Earth. And compare planets outside our Solar System with planets inside it. After all, WASP-80 b, being in orbit very close to its star, is a gas sphere shrouded in an atmosphere of methane. Just like the giants in our planetary system.