Gail Freeman

Telescopes have previously detected silicates in so-called brown dwarfs. These are essentially star-like objects that have failed to ignite properly. But this is a first for a planet-sized object.

To make the detection, Webb used its Mid-Infrared Instrument (Miri), part-built in the UK, and its Near-Infrared Spectrometer (NirSpec).

They didn't take pretty pictures of the planet, at least not in this instance. What they did was tease apart the light coming from VHS 1256b into its component colours as a way to discern the composition of the atmosphere.

"JWST is the only telescope that can measure all these molecular and dust features together," said Miri co-principal investigator Prof Gillian Wright, who directs the STFC UK Astronomy Technology Centre, also in Edinburgh.

"The dynamic picture of the atmosphere of VHS 1256b provided by this study is a prime example of the discoveries enabled by using the advanced capabilities of Miri and NirSpec together."

JWST's primary mission is to observe the pioneer stars and galaxies that first shone just a few hundred million years after the Big Bang. But a key objective is to investigate exoplanets. In Miri and NirSpec it has the tools to study their atmospheres in unprecedented detail.

Scientists hope they might even be able to tell whether some exoplanets have conditions suitable to host life.

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.

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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."

Telescopes have previously detected silicates in so-called brown dwarfs. These are essentially star-like objects that have failed to ignite properly. But this is a first for a planet-sized object.

To make the detection, Webb used its Mid-Infrared Instrument (Miri), part-built in the UK, and its Near-Infrared Spectrometer (NirSpec).

They didn't take pretty pictures of the planet, at least not in this instance. What they did was tease apart the light coming from VHS 1256b into its component colours as a way to discern the composition of the atmosphere.

"JWST is the only telescope that can measure all these molecular and dust features together," said Miri co-principal investigator Prof Gillian Wright, who directs the STFC UK Astronomy Technology Centre, also in Edinburgh.

"The dynamic picture of the atmosphere of VHS 1256b provided by this study is a prime example of the discoveries enabled by using the advanced capabilities of Miri and NirSpec together."

JWST's primary mission is to observe the pioneer stars and galaxies that first shone just a few hundred million years after the Big Bang. But a key objective is to investigate exoplanets. In Miri and NirSpec it has the tools to study their atmospheres in unprecedented detail.

Scientists hope they might even be able to tell whether some exoplanets have conditions suitable to host life.

Astronomers are reporting Webb's observations of VHS 1256b in The Astrophysical Journal Letters.

James Webb is a collaborative project of the US, European and Canadian space agencies. It was launched in December 2021 and is regarded as the successor to the Hubble Space Telescope.

It's being described as the most detailed ever map of the influence of dark matter through cosmic history.

A telescope in Chile has traced the distribution of this mysterious stuff on a quarter of the sky and across almost 14 billion years of time.

The result is once again a spectacular confirmation of Einstein's ideas.

Although dark matter makes up about 85% of all mass in the Universe, it's extremely difficult to detect and defies a ready description.

But dark matter influences the large scale structure of everything we see - where all the galaxies are, where the voids in space are. It's the scaffolding on which the visible structure of the Universe is hung.

It neither emits nor absorbs light. The only way you can very obviously infer its presence is through its interplay with gravity.

Big rotating galaxies of stars would fly apart were it not for the inclusion of some unseen mass pulling on them and keeping them intact.

But dark matter will bend, or lens, background light, and this is how its whereabouts was mapped by the Atacama Cosmology Telescope (ACT).

Nasa engineers have been practising how the tubes, currently in the belly of Perseverance, will be ejected. They have a full-sized copy of the rover at JPL on which to simulate manoeuvres before sending up commands to Mars to carry out the actions for real.

A go/no-go decision is expected to be made by Nasa following a meeting on 19 October.

It may be that this first depot dropped by Perseverance becomes an insurance back-up, to be collected for return to Earth only if the rover suffers a catastrophic failure on the rest of its mission.

Scientists want to collect many more samples, in which case the retrieval plan may focus on where the robot goes in future.

A final determination will be driven by events on Mars.

Lori Glaze, the director of Nasa's planetary science division, lauded the "incredible Perseverance team" for the mission achievements so far.

"We not only went to the right place, but we sent the right spacecraft with the right science instruments to explore this amazing ancient environment on Mars," she told reporters.