Here this fine morning, and in the masthead, we see something no human eye has ever observed before: the fine details, of the dust accretion disks that ultimately congeal by the force of gravity, into rings, and then planetary bodies, around a star as it ages in place. We see at right, in many ways, back in time -- to our own Sol's "baby photos" -- the earliest days of our own solar system, and how the Kuiper Belt may have formed -- and remained a "debris belt", while each of Saturn, Jupiter and Neptune (and the rest) ultimately assembled into. . . solid planets.
. . .Hubble, ALMA, and [H2] are tag-teaming to assemble a holistic view of the debris disks around a number of 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 [H2] 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.”
These belts most likely are carved by the gravitational forces produced by unseen planets. Similarly, inside 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 shepherded by as-yet-unseen bodies beyond it. As [H2] images more systems, we will learn about the configurations of their planets.
Fomalhaut's 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 previous and longer-wavelength observations using submillimeter telescopes on Mauna Kea, Hawaii, NASA’s Spitzer Space Telescope, and Caltech's Submillimeter Observatory.
“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 [H2'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,” added Wolff. “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!’”
[H2] also imaged what Gáspár dubs “the great dust cloud,” which may be evidence for a collision occurring in the outer ring between two protoplanetary bodies. This is a different feature from a suspected planet first seen inside the outer ring by Hubble in 2008. Subsequent Hubble observations showed that by 2014 the object had vanished. A plausible interpretation is that this newly discovered feature, like the earlier one, is an expanding cloud of very fine dust particles from two icy bodies that smashed into each other. . . .
Now you know. . . be excellent to one another, all you shepherd-, and shepherded- moons. . . .
नमस्ते
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