Using VLT, researchers discovered barium, the hardest element ever found in the upper atmosphere of two hot exoplanets like Jupiter.
In the atmosphere of two gas exoplanet giants, WASP-76b and WASP-121b, the worst element ever found in that environment was detected.
The two planets are already unusual. Both planets are known as ultra-hot Jupiters: they are comparable in size to Jupiter, but their surface temperature exceeds 1,000 °C because of proximity to the host star. This gives these planets characteristics that are quite unusual: for example, the WASP-76b astronomers suspect that it is raining iron.
Why is the bar so high?
Despite the knowledge that these planets are different from many others, scientists were surprised to find barium, which is 2.5 times heavier than iron, high in the atmosphere.
We sometimes see this chemical element in our sky, for example, a bright green color in fireworks, but now the question for scientists is, what kind of natural process could bring this heavy element to such a high altitude? What mechanisms do we have to do with this? Moreover, the fact that this chemical element has been detected in the atmospheres of both super-hot players suggests that this category of planets may be even more strange than previously thought.
Composition of the atmosphere
In order to determine the composition of the atmosphere, the exoplanet requires very specialized equipment. The team used an ESPRESSO VLT instrument to analyse the star light that passed through the WASP-76b and WASP-121 b atmospheres. This made it possible to clearly detect several elements, including bariums.
The exoplanet exoplanet of ultra-hot Jupiters is extremely useful to study. In fact, being gaseous and hot, their atmosphere is very vast and therefore easier to observe and study than the atmosphere of smaller or colder planets.
By means of future instruments such as the high-resolution echele spectrogram ArmazoNes High Activity Echelle Spectrogram, astronomers will be able to study the atmospheres of large and small exoplanets, including even on rocky planets like Earth, and at much greater depths, to gather more and more clues about the mysterious nature and composition of these strange worlds so different from our own.