Researchers who observe space with the james webb space telescope from NASA have identified characteristics of silicate clouds in the atmosphere of a distant planet. The atmosphere is constantly rising, mixing and shifting during its 22-hour day, carrying the hottest material up and down. pushing the cooler material down.
Los resulting changes in brightness are so dramatic that it is the planetary mass object more variable that has been known to date. The team, led by Brittany Miles from the University of Arizona, also detected water, methane y carbon monoxide with Webb’s data, and found evidence of carbon dioxide. This is the largest number of molecules ever identified on a planet at once. outside our solar system.
listed as VHS 1256 bthe planet is about 40 light years away and its orbit revolves around two stars over a period of 10,000 years. “VHS 1256 b is about four times farther from its stars than Pluto is from our Sun, making it an excellent target for Webb,” said Miles.
“That means the light from the planet doesn’t mix with the light from its stars.” Higher up in its atmosphere, where silicate clouds churn, temperatures reach a blistering 830 degrees Celsius (1,500 degrees Fahrenheit).
The planet VHS 1256 b is quite young, only 150 million years have passed since its formation, and it will continue to change for billions of years.
Within those clouds, Webb detected larger and smaller silicate dust grains, shown in a spectrum. “The finer silicate grains in its atmosphere might look more like tiny smoke particles,” said co-author Beth Biller, of the University of Edinburgh in Scotland. “Larger grains could be more like very hot, very small sand particles.”
VHS 1256 b tiene low gravity compared to the brown dwarfs more massive, meaning its silicate clouds can appear and linger higher in its atmosphere, where Webb can detect them.
troubled skies
Another reason why its skies are so turbulent is the age of the planet. In astronomical terms, it is pretty young. Only 150 million years have passed since its formation and it will continue to change and cool for billions of years.
In many ways, the team believes these findings are the first “coins” drawn from a spectrum that researchers see as a data trove. Because they have barely begun to identify its content.
A team from the University of Arizona used two instruments known as spectrographs aboard the James Webb Space Telescope. / NASA, ESA, CSA, J. Olmsted (STScI)
“We have identified silicates, but to better understand what grain sizes and shapes match with what specific types of clouds it’s going to require a lot of additional work,” Miles said. “This is not the last word on this planet: it is the beginning of a large-scale modeling effort to fit Webb’s complex data,” he added.
Although all of the features the team observed have been detected by other telescopes on other planets, at different locations in the Milky Way, the other research teams generally identified only one feature at a time.
“no other telescope has identified so many features at once for a single target,” said co-author Andrew Duskfrom the University of California at Santa Cruz. “We are seeing many molecules in a single Webb spectrum, detailing the dynamic cloud and weather systems on this planet.”
Although similar features had been detected on other planets, at various locations in the Milky Way, research teams generally identified one feature at a time.
The team reached these conclusions by analyzing data known as spectra, collected by of the instruments aboard Webb: the Near Infrared Spectrograph (NIRSpec) and the Mid Infrared Instrument (MIRI).
Because the planet’s orbit moves such a great distance from its stars, the researchers were able to observe it directly, rather than using the transit technique or a coronagraph to obtain these data.
There will be much more to learn about VHS 1256 b in the coming months and years as this team, and others, continue to analyze Webb’s high-resolution infrared data. “There’s a lot of performance in a very modest amount of telescope time,” Biller said. “With just a few hours of observations, we have what seems like endless potential for additional discoveries,” he added.
far from their stars
What could happen to this planet billions of years from now? Since it is so far from its stars, it will get colder over time and their skies could go from cloudy to clear.
The researchers observed VHS 1256 b as part of Webb’s First Science Observations program, which is designed to help transform the astronomical community’s ability to characterize planets and the disks where they form.
Since it is so far from its stars, the planet will get colder over time and its skies could go from cloudy to clear.
The team’s scientific paper, titled “The James Webb Space Telescope First Science Observations Program for Direct Observations of Exoplanetary Systems II: 1-20 Micron Spectrum of Planetary-Mass Companion VHS 1256-1257 b,” was published this week. in The Astrophysical Journal Letters .
Finally, it should be remembered that the James Webb Space Telescope is the world’s leading space science observatory. Webb’s mission is to see beyond distant worlds around other stars and explore still enigmatic structures, as well as the origins of our universe. In this international program led by NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA) are partners.
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