The James Webb Space Telescope (JWST) has discovered that 1,000-mph winds are blowing a shower of tiny quartz crystals through the hot, silicate-enriched atmosphere of a distant gas giant planet called WASP-17b.
“We learned from Hubble [Space Telescope] “Our observations suggest that there must be aerosols – small particles that form clouds or fog – in the atmosphere of WASP-17b, but we did not expect them to be made of quartz,” says Daniel Grant of the University of Bristol in the UK and leader of the research team. new. A study said about the discovery in A statement.
WASP-17b is an incredible world. It orbits its star every 3.7 days at a distance of only 7.8 million kilometers (4.9 million miles) from its star, which is located 1,300 light-years from our planet. LandWASP-17b is so close to its stellar host that its daytime temperature rises to 1,500 degrees Celsius (about 2,700 degrees Fahrenheit). Because the atmosphere is so hot on this exoplanet, the world has actually expanded to about 285,000 kilometers (176,892 miles), which is nearly twice as much as Diameter of Jupiter. This is despite the fact that WASP-17b only contains about half JupiterTotal mass. WASP-17b is one of the most “puffy” planets known – and its puffy atmosphere makes it a great target for the James Webb Space Telescope.
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Grant and his fellow astronomers watched WASP-17b transit its star using JWST’s mid-infrared instrument (MIRI). As the exoplanet moved in front of its star from the viewpoint of the James Webb Space Telescope, MIRI detected starlight that was blocked by the bulge planet itself but partly absorbed by the world’s atmosphere. Such measurements lead to what is called a transmission spectrum, where certain wavelengths are blocked by certain molecules in the atmosphere.
Like Jupiter, WASP-17b appears to be composed mostly of hydrogen and helium. In addition, MIRI detected carbon dioxide and water vapor, and at a wavelength of 8.6 microns, the absorption signature of pure quartz crystals. Along with previous notes with Hubble Space TelescopeThese crystals are believed to be shaped like pointed hexagonal prisms like quartz on Earth, but their size does not exceed 10 nanometers.
Quartz is a form of silicates, which are minerals rich in silica and oxygen. Silicates are exceptionally common: all rocky bodies in the solar system are made of them, and silicates have previously been detected in the atmospheres of hot exoplanets before. However, in those cases the olivine and pyroxene crystals were more complex and rich in magnesium.
“We were fully expecting to see magnesium silicate,” said Hannah Wakeford from Bristol. “But what we see instead are more likely the building blocks of those particles, as the small seed particles needed to form the larger silicate grains we detect in cold exoplanets and brown dwarfs.”
WASP-27b is also tidally locked, meaning it always shows the same face to its star. As winds blow around the planet, carrying quartz nanoparticles with them, they form high-altitude fog — essentially diffuse clouds of rock crystals — in the region where day and night end. These fogs then venture to the dayside, evaporating in the heat.
Grant explained how silicate crystals become embedded in the planet’s atmosphere in the first place.
He said: “WASP-17b is very hot… and the pressure at which quartz crystals form high in the atmosphere does not exceed about one thousandth of what we see on the Earth’s surface.” “Under these conditions, solid crystals can form directly from the gas, without going through a liquid phase first.”
The results were published in October Astrophysical Journal Letters.
