The James Webb Telescope sees a new asteroid belt – another star in the Solar System

Stars can be seen with the naked eye, but planets orbiting other stars are incredibly difficult to see, even with the most powerful telescopes ever made. It wasn’t until 1992 that astronomers imaged an exoplanet, meaning a planet in another solar system; Before that, some astronomers thought that our solar system might be unique and that planets were probably rare.

However, by 2010, exoplanet discoveries had become frequent enough to be quotidian; Now, according to NASA, there are more than 9,000 possible or confirmed exoplanets. Due to a selection bias favoring massive bodies close to their parent stars, many of these planets are larger than Jupiter. Smaller bodies are much harder to see – and when it comes to bodies smaller than planets, such as the Moon or asteroids, none of the candidate bodies are actually confirmed.

That makes the discovery of an asteroid belt orbiting the Fomelhot star all the more exciting. Thanks to new observations made using the James Webb Space Telescope (JWST), we have a better sense of the nature of the Solar System around Fomelhot, one of the brightest stars in the Southern Hemisphere’s night sky and some of the more sedentary stars. It is 25 light years away from Earth. In fact, although astronomers expected to see similar intricate details between our solar system and the Fomalhout star system, they were surprised to find that it is more complicated than previously thought, as they discovered that it has an unexpectedly convoluted asteroid belt.

The observations were officially published in a May 8 report in Nature Astronomy. Previously, the Hubble Space Telescope and the Herschel Space Observatory, as well as the Atacama Large Millimeter/Submillimeter Array (ALMA), have taken detailed images of the outer asteroid belt in the Fomalhot star system. Thanks to JWST, astronomers are now able to see the inner bands for the first time, revealing a bunch of surprises.

In an interview with Salon, Andras Gaspar, lead author of the paper and an astronomer at the University of Arizona in Tucson, said there is “so much to unpack” from this one observation.

“We originally predicted that we would see a very narrow asteroid belt,” Gaspar said. But instead they found three nested belts stretching about 12 million kilometers (14.3 billion miles), 150 times the distance between the Sun and Earth. “There are no gas giants orbiting nearby,” he said, adding that the solar system includes Jupiter and Saturn. “But we see more gaps [out]But it roughly corresponds to the orbit of our Neptune … which is a good sign that there might be an ice giant orbiting there.”

Harvard astronomer Avi Loeb, who was not involved in the study, called the observation “exciting.”

“[They show] For the first time, three nested belts in a dusty debris disk around a young, hot star beyond the scale of our own planetary system,” Loeb said. “Dust particles in the belts are mostly gravitationally shepherded by unseen planets. So far.”

Loeb said the situation in space is similar to observing ripples “on the surface of a muddy pond” on Earth, suggesting the existence of fish “hidden from view under the water.”

In fact, our solar system’s asteroid belt is considered a “failed planet”; There are many smaller globular bodies that make up the asteroid belt, including Ceres, Vesta, and Pallas. But none have enough gravity to solidify into a large planet. That process of planet formation, in which debris accumulates slowly enough to accumulate and then clear its orbital lane, is believed to have taken place during the formation of all other planets in our solar system.

Yet our own asteroid belt is influenced by planets, including asteroids orbiting in Jupiter’s shadow, known as Trojans. Astronomers believe that the debris disks outside the Fomalhot star system were also formed by unseen planets.

“We certainly didn’t expect a more complex structure with a second intermediate belt and then a broader asteroid belt,” Schuyler Wolff, another member of the University of Arizona team, said in a media statement. “That structure is very exciting, because any time an astronomer sees gaps and rings in a disk, they say, ‘There could be an embedded planet forming the rings!

Part of JWST’s mission is to peer into the far corners of the universe and survey the atmospheres of Earth-like exoplanets — or at least identify them. When it comes to Phomalhot, there are lessons to be learned about how our own solar system and its planets formed.

Gaspar told Salon that based on JWST’s observations, this star system is “really chaotic” and has a lot of “dynamic activity going on.”

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“We see this inner disk at a distance from the other one, so these are all signs [that] The system is dynamically very active,” Gaspar said. “Like our solar system, early in its life, at roughly the same age, there are ideas that it underwent some dynamical reorientation — causing massive bombardments — so it could be analogous to what happened in the early solar system.”

Gaspar said the early stages of planetary formation could be a violent time of billions of years.

“And it’s interesting, because some life evolved on Earth after the first billion years,” Gaspar said.

In other words, if there was still enough chaotic activity in the evolution of the planetary system, it would prevent life from forming.

The next step, Loeb said, is to take a more detailed picture of the star system and see if the hidden planets that form the nested belts can be identified.

“The planetary system is very different from the Solar System in that it is likely to have more than one giant planet,” he said.