James Webb discovers three asteroid rings around a distant star

James Webb just wanted to capture the dust ring of the star Fomalhaut. Instead, he found three huge structures.

The unprecedented infrared resolution of the James Webb Space Telescope has revealed three huge dust belts around a nearby young star, Fomalhaut.

The goal was to study the first asteroid belt seen outside our solar system in infrared light. But to his surprise, the dusty structures are much more complex than those of Kuiper and our solar system.

In general, there are three nested belts that extend 23 billion kilometers from the star; That’s 150 times the distance from Earth to the Sun.

The scale of the outermost belt is about twice the scale of the Kuiper Belt of our small-body, cold-dust solar system beyond Neptune.

The inner belts, which have never been seen before, were revealed by Webb for the first time.

A big surprise.
The belts surround the hot young star, which can be seen with the naked eye as the brightest star in the southern constellation Piscis Austrinus.

Dust belts are the debris from the collisions of larger bodies, analogous to asteroids and comets, and are often described as “debris disks” to those we have in our own planetary system,” András explains in a statement. Gáspár of the University of Arizona in Tucson and lead author of a new paper describing these results.

“By looking at the patterns in these rings, we can start to make a little sketch of what a planetary system might look like, if we could image deep enough to see the possible planets.”

The Hubble Space Telescope and Herschel Space Observatory, as well as the Atacama Large Millimeter/submillimeter Array (ALMA), have previously taken sharp images of the outermost belt. However, none of them found any structure inside it.

The inner belts have been solved for the first time by James Webb in infrared light.

“Where Webb really excels is that we are able to physically resolve the thermal glow of dust in those inner regions.

So you can see inner belts that we could never see before,” said Schuyler Wolff, another member of the University of Arizona team.

Hubble, ALMA and Webb are teaming up to assemble a holistic view of the debris disks around various stars.

“With Hubble and ALMA, we were able to image a bunch of Kuiper belt analogues and have learned a lot about how outer disks form and evolve,” Wolff said.

These belts are most likely carved by the gravitational forces produced by unseen planets.

Similarly, within our solar system, Jupiter corrals the asteroid belt, the inner edge of the Kuiper belt is sculpted by Neptune, and the outer edge could be guided by as-yet-unseen bodies beyond.

As James Webb images more systems, we will learn about the configurations of their planets.

The Fomalhaut dust ring was discovered in 1983 in observations made by NASA’s Infrared Astronomical Satellite (IRAS).

The existence of the ring has also been inferred from earlier, longer-wavelength observations using submillimeter telescopes on Mauna Kea, Hawaii, NASA’s Spitzer Space Telescope, and the Caltech Submillimeter Observatory.