Roughly 1,000 light-years away from Earth, a gigantic disk of gas and dust is swirling around a young star and giving rise to new planets. Not only is it the largest planet-forming disk astronomers have ever found, its behavior is different than any seen before.
The disk spans nearly 400 billion miles (640 billion kilometers)—that’s about 40 times wider than our entire solar system. While it was first identified in 2016, astronomers have now used NASA’s Hubble Space Telescope to capture the first image of this planetary nursery in visible light. The new images revealed an unusually chaotic environment, with wisps of material stretching farther above and below the disk than expected. Strangely, these extended filaments are concentrated on just one side of the disk.
The team published its findings on December 23 in The Astrophysical Journal, including a nickname for the baffling space object: “Dracula’s Chivito,” a nod to the heritage of two of the researchers, one from Transylvania (home of Dracula) and one from Uruguay (home of the chivito, an iconic beefsteak sandwich). When viewed edge-on, the planet-forming disk resembles a sandwich, with a dark central lane flanked by white top and bottom layers of gas and dust.
“The level of detail we’re seeing is rare in protoplanetary disk imaging, and these new Hubble images show that planet nurseries can be much more active and chaotic than we expected,” Kristina Monsch, study lead author and a postdoctoral researcher at the Center for Astrophysics (CfA), a collaboration between Stanford University and the Smithsonian, said in a NASA statement.
“We’re seeing this disk nearly edge-on and its wispy upper layers and asymmetric features are especially striking,” she added.
A lopsided celestial sandwich
All planets form from disks of gas and dust encircling young stars. Astronomers have long believed that these protoplanetary disks were relatively orderly, serene environments where planets gradually coalesce over millions of years. Recent studies have challenged that assumption, pointing to greater complexity and diversity among these systems. Hubble’s new image of Dracula’s Chivito adds to this growing body of evidence.
“We were stunned to see how asymmetric this disk is,” co-author Joshua Bennett Lovell, also an astronomer at the CfA, said in the statement. “Hubble has given us a front row seat to the chaotic processes that are shaping disks as they build new planets—processes that we don’t yet fully understand but can now study in a whole new way.”
The fact that Dracula’s Chivito’s extended filaments only appear on one side suggests that dynamic processes—like gas and dust falling into the disc, or other interactions with the space outside it—are shaping the celestial sandwich.
A model for the early solar system
The disk obscures the young star (or stars) within it, but the researchers believe it could harbor either a single massive, hot star or a binary pair. The disk itself contains 10 to 30 times more mass than Jupiter, meaning there’s enough material to form multiple gas giant planets. As such, Dracula’s Chivito is basically a scaled-up model of what our solar system looked like 4.6 billion years ago.
“In theory, [Dracula’s Chivito] could host a vast planetary system,” Monsch said. “While planet formation may differ in such massive environments, the underlying processes are likely similar. Right now, we have more questions than answers, but these new images are a starting point for understanding how planets form over time and in different environments.”
Dracula’s Chivito is therefore a natural laboratory for studying planet formation, says Monsch. Hubble and other space telescopes, such as NASA’s James Webb, will continue observing this unique disk to uncover what’s shaping its bizarre structure.
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