Astronomers using ground-based telescope VLT has confirmed that on the night side Altragracia gas giant WASP-76b rains drops of iron. This allows you to accurately simulate the atmosphere of such objects and learn more about their origin and evolution, reported the website of the European southern Observatory.
WASP-76b was discovered in 2013 and is situated at a distance of about 640 light-years from Earth in the constellation of Pisces, the star of spectral class F7, which is 1.5 times heavier and 1.7 times greater than the Sun. Vergaray exoplanet is a gas giant and makes one revolution around its star for 1.8 earth days, while it is tidal capture, which means that on one side there is eternal day and the other always in shadow. The outer hot layers of such exoplanets have ideal conditions for the study of chemical processes occurring in such extreme conditions that shape the climate on these gas giants.
New observations of WASP-76b was conducted in September and October 2018 with a receiver, ESPRESSOset on the complex telescopes, VLT in Chile. Astronomers led by David Arequipa (David Ehrenreich) has observed two events of the transit of the planet across the stellar disk and received the transmission spectrum. When the planet is between the earth observer and the stellar disk, part of the light from the star passes through the atmosphere and is absorbed by various chemical elements, which is reflected in the spectra and allows to understand the chemical composition of the atmosphere.
The temperature of the outer layers of the exoplanet on the light side was estimated at 2693 Kelvin, at night it drops to 1795 Calvin. Thus, in the region of the terminator (the border day and night) is practically not observed atomic iron, while on the light side it is logged. This is because on the day side of the planet, no clouds and a lot of atomic iron vapour in the atmosphere, which a powerful wind is transferred to the night side. There, in turn, the processes of vapor condensation and formation of clouds of droplets of iron. Thus, the idea that in the night WASP-76b, and other similar exoplanets can rain from the drops of iron was confirmed.
We have previously described how in the atmosphere of exoplanets for the first time found aluminum oxide and titanium oxide, as well as why red dwarf and hot Jupiter does not fit in the expectations of astronomers.