New observations with the James Webb Space Telescope directly confirm that some alien planets have rocky clouds.
According to the International Group of Astronomers, the telescope has directly observed silicate clouds in the atmosphere of a brown dwarf. According to the researchers, such a discovery was made for the first time in history in a planetary mass companion outside the solar system.
According to the group, the results are not only e. year Not only will it help us better understand the stars, but it’s just a preview of what James Webb is capable of.
The publication has already been submitted to AAS journals and is currently available on the peer-reviewed server arXiv.
We’ve already seen James Webb’s candid photo of an exoplanet, but a brown dwarf is something else.
Such objects appear when the “infant” star cannot accumulate enough mass to start hydrogen synthesis in the core; As a result, they occupy the mass range between the largest planets and the faintest stars.
However, brown dwarfs are about 13.6 times the mass of Jupiter (sorry Jupiter, you tried that too, but it didn’t work) and can synthesize deuterium, or heavy hydrogen—that is, hydrogen that has a proton and a neutron in its core instead of just one proton.
The fusion pressure and temperature of deuterium are lower than that of hydrogen, which means that brown dwarfs are a kind of “light” star.
That is, unlike exoplanets, brown dwarfs emit their own heat and light. Much less than stars, of course, but it can be observed directly, especially in the infrared wavelengths in which James Webb specializes.
A team of scientists at the University of California, Santa Cruz, led by astronomer Brittany Miles, made observations of a brown dwarf called VHS 1256-1257 b, located about 72 light-years away, first described in 2015.
It has about 19 Jupiter masses and is relatively young; It is characterized by a reddish foggy atmosphere.
In the past, this nebula was associated with clouds of young brown dwarfs; So the team took infrared spectra to see if they could figure out the composition of the brown dwarf.
This is based on the fact that different elements absorb and re-emit different wavelengths. Scientists can see the dark and bright features in the spectrum and identify the elements that cause them.
The team found that the composition of VHS 1256-1257 b was similar to other brown dwarfs studied in the infrared, but much more distinct.
“Based on a comparison of other sample brown dwarf spectra, molecular opacities, and atmospheric models, we observed water, methane, carbon dioxide (CO), carbon dioxide, sodium, and potassium in the spectrum obtained by James Webb,” the researchers wrote.
According to them, the characteristic of carbon dioxide is the clearest ever seen. As hoped, they also spotted the clouds—the long-predicted clouds of a thick layer of silicon particles the size of grains of sand smaller than a micron. According to the researchers, these are probably minerals such as forsterite, enstatite, or quartz.
It seems that this may finally prove that young brown dwarfs are surrounded by silicate clouds that influence their brightness variations.
This allows us to interpret observations of brown dwarfs in the future.
The study is available on the peer-reviewed server arXiv.
Prepared by ScienceAlert.
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