A raging dust storm has been observed on a planet outside our Solar System for the first time.
It was detected on the exoplanet known as VHS 1256b, which is about 40 light-years from Earth.
It took the remarkable capabilities of the new James Webb Space Telescope (JWST) to make the discovery.
The dust particles are silicates – small grains comprising silicon and oxygen, which form the basis of most rocky minerals.
“But the storm detected by Webb isn’t quite the same phenomenon you would get in an arid, desert region on our planet. It’s more of a rocky mist.
It’s kind of like if you took sand grains, but much finer. We’re talking silicate grains the size of smoke particles,” explained Prof Beth Biller from the University of Edinburgh and the Royal Observatory Edinburgh, UK.
“That’s what the clouds on VHS 1256b would be like, but a lot hotter. This planet is a hot, young object. The cloud-top temperature is maybe similar to the temperature of a candle flame,” she told BBC News.
VHS 1256b was first identified by the UK-developed Vista telescope in Chile in 2015.
It’s what’s termed a “super Jupiter” – a planet similar to the gas giant in our own Solar System, but a lot bigger, perhaps 12 to 18 times the mass.
It circles a couple of stars at great distance – about four times the distance that Pluto is from our Sun.
Earlier observations of VHS 1256b showed it to be red-looking, hinting that it might have dust in its atmosphere. The Webb study confirms it.
“It’s fascinating because it illustrates how different clouds on another planet can be from the water vapour clouds we are familiar with on the Earth,” said Prof Biller.
“We see carbon monoxide (CO) and methane in the atmosphere, which is indicative of it being hot and turbulent, with material being drawn up from deep.
“There are probably multiple layers of silicate grains. The ones that we’re seeing are some of the very, very fine grains that are higher up in the atmosphere, but there may be bigger grains deeper down in the atmosphere.”
( Source BBC)
