Astronomers using NASA’s James Webb Space Telescope to photograph a nearby young star, Fomalhaut, to study the first asteroid belt ever seen outside our solar system got much more than they bargained for.
According to NASA’s Jet Propulsion Laboratory, the dusty structures are much more complex than the asteroid and Kuiper dust belts in our solar system than previously thought.
In addition, the scale of the outermost belt is about twice the scale of our solar system’s Kuiper Belt of small bodies and cold dust found beyond Neptune.
The inner belts, which have never been seen before, were revealed in an image from the James Webb Space Telescope for the first time.
Fomalhaut, which NASA says is a "young" star, can actually be seen with the naked eye here on Earth as the brightest star in the southern constellation Piscis Austrinus.
The three dusty belts surrounding Fomalhaut are debris from collisions of larger bodies analogous to asteroids and comets. They’re frequently described as "debris disks," according to NASA.
"I would describe Fomalhaut as the archetype of debris disks found elsewhere in our galaxy because it has components similar to those we have in our own planetary system," said András Gáspár of the University of Arizona in Tucson and lead author of a new paper describing these results.
Gáspár added that looking at the patterns in the rings could show what a planetary system should look like if photos could show details deep enough to see the suspected planets.
Previously, the Hubble Space Telescope and Herschel Space Observatory, as well as the Atacama Large Millimeter/submillimeter Array (ALMA), have all produced sharp images of the outermost belt, but none of them were able to find structures within it.
The inner belts have now been resolved for the first time by the James Webb Space Telescope in infrared light.
"Where Webb really excels is that we’re able to physically resolve the thermal glow from dust in those inner regions. So you can see inner belts that we could never see before," said Schuyler Wolff, another team member at the University of Arizona.
Now, Hubble, ALMA and the James Webb Space Telescope are tag-teaming to assemble a new view of the debris disks around several stars.
"With Hubble and ALMA, we were able to image a bunch of Kuiper Belt analogs, and we’ve learned loads about how outer disks form and evolve," said Wolff. "But we need Webb to allow us to image a dozen or so asteroid belts elsewhere. We can learn just as much about the inner warm regions of these disks as Hubble and ALMA taught us about the colder outer regions."
NASA says gravitational forces produced by unseen planets likely carved the belts. And as the James Webb Space Telescope photographs more systems, astronomers will learn more about the configurations of their planets.
"The belts around Fomalhaut are kind of a mystery novel: Where are the planets?" said George Rieke, another team member and U.S. science lead for Webb’s Mid-Infrared Instrument (MIRI), which made these observations. "I think it’s not a very big leap to say there’s probably a really interesting planetary system around the star."