In just a few hours of observation, the space telescope discovered a dynamic atmosphere on a planet 40 light-years from Earth.
Silicate cloud structures in the atmosphere of a distant planet have been detected by scientists using NASA's James Webb Space Telescope. The atmosphere is constantly rising, mixing, and flowing throughout the 22-hour day, pushing colder matter down and pulling warmer matter up. It is the most variable planetary-mass object to date, as the accompanying brightness changes are so abrupt.
Using data from James Webb, the researchers also made incredibly sensitive detections of water, methane and carbon monoxide, and discovered evidence of carbon dioxide. This is the largest number of molecules ever discovered at once on a planet outside our solar system.
The planet, designated VHS 1256 b, orbits not one but two stars over a 10.000-year period and lies about 40 light-years away. According to Miles, VHS 1256 b is an excellent target for Webb because it's nearly four times as far from their star as Pluto is from the Sun. This shows that the light of the planet is not diluted by the light of its stars. In its atmosphere, where silicate clouds are fused, temperatures rise to 830 degrees Celsius.
Webb discovered silicate dust particles of various sizes within these clouds, which were shown on a spectrum. Co-author with professor Beth Biller of the University of Edinburgh in Scotland noticed that finer silicate grains in the atmosphere can resemble tiny smoke particles.
“Larger grains may be more like hot, small particles of sand.”
Unlike the more massive brown dwarfs, VHS 1256 b has a low gravity, allowing silicate clouds to form and stay higher in its atmosphere where Webb can detect them. The age of the planet is another factor contributing to the turbulent skies. It is quite new from an astronomical point of view. It formed only 150 million years ago and will continue to evolve and cool for billions of years.
The team sees these results as the first "coins" discovered in what scientists call an information-rich spectrum. They're just beginning to identify what's inside. According to Miles, we found silicates, but more research is needed to determine which grain sizes and shapes correspond to different cloud types. This is just the beginning of a major modeling effort suited to Webb's complex data, so it's not the last word on this planet.
Other work teams often detected only one feature at a time, even though all the features the team witnessed were discovered by other observatories on other planets elsewhere in the Milky Way.
According to co-author Andrew Skemer of the University of California at Santa Cruz, no other telescope has "detected so many features for a single target at once." Earth's dynamic cloud and weather systems are revealed by multiple molecules in a single Webb spectrum.
The Near Infrared Spectrograph (NIRSpec) and Intermediate Infrared Instrument at Webb provided the researchers with data known as the spectrum they used to arrive at these conclusions.
(MIRI). Instead of using the transit technique or the coronagraph to collect this data, the researchers were able to directly image the planet because the planet orbits its stars at a fairly long distance.
Over the coming months and years, there will be more to discover about VHS 1256 b as this team and others scan Webb's high-resolution infrared data. Biller continued: “The time of a very small telescope has a tremendous payoff. “With just a few hours of observations, we have endless potential for further exploration,” he writes.
What could happen to this planet in the next billions of years? Because it is so far away from its stars, it will eventually cool and the sky may change from cloudy to clear.
As part of Webb's Early Broadcast Science initiative, which aims to revolutionize the scientific community's capacity to identify planets and the disks from which they form, researchers spotted VHS 1256 b.
Source: jpl.nasa.gov/news
Günceleme: 23/03/2023 18:16