Astronomers Spot Largest Protoplanetary Disk Ever Observed around Young Star

The protoplanetary disk around IRAS 23077+6707, a young star about 1,000 light-years away, is surprisingly chaotic and turbulent, with trails of material extending much farther above and below the disk than astronomers have seen in a similar system.

This Hubble image shows a protoplanetary disk around IRAS 23077+6707. Image credit: NASA / ESA / STScI / K. Monsch, CfA / J. DePasquale, STScI.

Protoplanetary disks are circumstellar disks rich in dust and gas, present around young stars and are expected to be the main sites of planet formation.

The disk of IRAS 23077+6707 extends nearly 644 billion kilometers (400 billion miles), or about 40 times the diameter of our solar system, to the outer edge of the Kuiper Belt of cometary bodies.

The disk obscures the star inside it, which scientists believe could be either a hot, massive star or a pair of stars.

And this enormous disk is not only the largest known planet-forming disk; this is also shaping up to be one of the most unusual.

“The level of detail we see is rare in imaging protoplanetary disks, and the new Hubble images show that planet nurseries can be much more active and chaotic than expected,” said Dr. Kristina Monsch, an astronomer at the Harvard & Smithsonian’s Center for Astrophysics.

“We see this disk almost edge-on and its wispy upper layers and asymmetrical features are particularly striking.

The NASA/ESA Hubble Space Telescope and the NASA/ESA/CSA James Webb Space Telescope have both seen similar structures on other disks, but IRAS 23077+6707 gives us an exceptional perspective, allowing us to trace its substructures in visible light with an unprecedented level of detail.

This makes the system a unique new laboratory for studying planet formation and the environments in which it occurs.

The rimmed disk resembles a hamburger, with a dark central lane flanked by bright upper and lower layers of dust and gas.

The impressive height of these features isn’t the only thing that has caught scientists’ attention.

The new images revealed that towering vertical filament-like features appear on only one side of the disk, while the other side appears to have a sharp edge and no visible filaments.

This particular, unbalanced structure suggests that dynamic processes, such as the recent fall of dust and gas, or interactions with its environment, are shaping the disk.

“We were amazed at how asymmetrical this disk is,” said Dr. Joshua Bennett Lovell, also of the Harvard & Smithsonian’s Center for Astrophysics.

“Hubble has given us a front-row seat to observe the chaotic processes that shape disks as they build new planets – processes that we don’t yet fully understand but can now study in a whole new way.”

All planetary systems form from disks of gas and dust surrounding young stars.

Over time, gas builds up on the star and planets emerge from the remaining material.

IRAS 23077+6707 could represent a larger-scale version of our first solar system, with a disk mass estimated to be 10 to 30 times that of Jupiter – enough material to form several gas giants.

This, added to the new discoveries, makes it an exceptional case for studying the birth of planetary systems.

“In theory, IRAS 23077+6707 could host a large planetary system,” Dr Monsch said.

“Although 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 provide a starting point for understanding how planets form over time and in different environments.”

The results will be published in the Astrophysics Journal.

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Kristina Monsch and others. 2025. Hubble reveals a complex multi-scale structure in the protoplanetary slice disc IRAS 23077+6707. ApJin press; arXiv:2510.11819