An alien world located just 70 light-years from Earth is one of the strangest worlds we’ve ever found. It reaches 20 Jupiter masses, has temperatures that can rapidly melt aluminum, and has a 10,000-year orbit around not one but two stars. And, oh yes: it is devastated by a constant, violent sandstorm. Astronomers have used the James Webb Space Telescope to get the most accurate observations ever of a planetary-mass object, revealing swirling clouds of silicate particles circulating in the atmosphere of a world called VHS 1256 b.

The discovery, published on the arXiv preprint server last year, has gone through the peer review process and will be published in 2019. Astrophysical Journal Letters. In addition, the team identified many components of VHS 1256 b’s atmosphere. These include clear detections of methane, carbon monoxide, and water, and additional evidence of carbon dioxide.

“No other telescope has detected so many features for a single target at once,” says astrophysicist Paul Moliere of the Max Planck Institute for Astronomy in Germany. “We see many molecules in a single spectrum from JWST detailing the planet’s dynamic cloud cover and weather systems.”

VHS 1256b is a bit of a mystery. Giant planets and brown dwarfs capable of fusing deuterium, a heavier hydrogen isotope whose mass is not large enough to fuse hydrogen, but which has a lower fusion temperature and pressure than hydrogen in their cores, cross the border between “failure stars.”

These two types of objects are believed to be shaped quite differently. Brown dwarfs typically form as stars that collapse from a dense knot of material within a cloud of gas and dust and then absorb more material to grow. Deuterium fusion is an intermediate step in the star’s growth process, but some stars – brown dwarfs – stop growing at this stage and stay as they are.

On the other hand, planets are thought to be formed from the bottom up, from material left over from star formation, and clump together to form a planet. This material is generally believed to be fairly close to the star. Although VHS 1256b’s large orbital distance to the two suns suggests it was formed by the collapse of a cloud, it is not diagnostic.

Theoretically, planets could also form from a cloud collapse pattern; The calculated minimum mass of the cloud collapse object is equal to one Jupiter. The boundary between a planet and a brown dwarf is thus the deuterium-burning mass boundary, so the exact nature of VHS 1256 b is unknown.

But it was this great distance that allowed such impressive observations.

“VHS 1256 b is about four times further from its star, Pluto, than our Sun, making it an excellent target for Webb,” said University of Arizona astronomer Brittany Miles, who led the international research team. “This means that the light of the planet does not mix with the light of its stars.”

The JWST’s observation range is infrared and near infrared, a range that includes thermal radiation. And VHS 1256b is very young, only 150 million years old, and still pretty hot due to its formation process. Its atmosphere, where sand clouds can be found, reaches 830 degrees Celsius (1,526 degrees Fahrenheit).