Extract from ABC News
Astronomers have used NASA's James Webb Space Telescope to reveal three debris belts around a nearby young star named Fomalhaut — the first such features seen outside of our solar system.
Key points:
- Fomalhaut is a young star that can be seen with the naked eye
- The star is surrounded by belts that extend out to 23 billion kilometres from it
- The belts are made up of debris from collisions of larger bodies
The three nested belts extend as far as 23 billion kilometres out from the star — 150 times the distance from Earth to the Sun.
Fomalhaut can be seen with the naked eye as the brightest star in the southern constellation Piscis Austrinus.
The dusty belts that surround it, frequently described as "debris disks", are made up of the ruins left by collisions of bodies such as asteroids and comets.
"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, the lead author of a new paper describing the results.
"By looking at the patterns in these rings, we can actually start to make a little sketch of what a planetary system ought to look like – If we could actually take a deep enough picture to see the suspected planets."
Other telescopes have previously taken sharp images of the outermost belts, but none of them were able to find any interior structures.
The Webb telescope was able to reveal the inner belts due to its use of 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," Schuyler Wolff, another member of the team at the University of Arizona, said.
Fomalhaut's dust ring was first discovered in 1983 by NASA's Infrared Astronomical Satellite (IRAS).
"The belts around Fomalhaut are kind of a mystery novel: Where are the planets?" said George Rieke, another team member and the US 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."
"We definitely didn't expect the more complex structure with the second intermediate belt and then the broader asteroid belt," Ms Wolff added.
"That structure is very exciting because any time an astronomer sees a gap and rings in a disk, they say, 'There could be an embedded planet shaping the rings!'"
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