About 1,000 light-years from Earth, a young star is wrapped in a planet-forming disk so enormous and misshapen that the astronomers who found it gave it a name part horror movie, part Uruguayan sandwich: Dracula’s Chivito.
Formally cataloged as IRAS 23077+6707, the disk stretches roughly 400 billion miles across. For scale, the Kuiper Belt extends to about 50 AU from the Sun, giving our solar system a diameter of roughly 9.3 billion miles at that boundary; the disk spans approximately 43 times that figure. Its northern half bristles with fang-like filaments of dust caught in scattered starlight. Its southern half, by contrast, is strangely bare. That dramatic mismatch, confirmed across multiple telescopes and wavelengths, makes it the largest and most lopsided protoplanetary disk on record, and it is pushing scientists to reconsider just how wild the planet-building process can get.
From survey image to record-breaker
The disk first turned up in images from the Pan-STARRS sky survey, where it appeared as an edge-on structure spanning about 11 arcseconds on the sky, unusually large for a disk of gas and dust around a young star. Astronomer Ciprian Berghea and colleagues used Gaia satellite data to pin down the distance and spectral analysis to classify the central object as a hot, late-A type star. Their findings, published in Astrophysical Journal Letters in 2024, established IRAS 23077+6707 as the biggest protoplanetary disk visible on the sky.
Follow-up observations with the Hubble Space Telescope’s Wide Field Camera 3, covering wavelengths from 0.4 to 1.6 micrometers, revealed a far more complex picture. The northern half of the disk is laced with prominent filaments of scattered light at multiple scales, while the southern half shows nothing comparable. That stark north-south contrast is the system’s defining feature, and it has been detailed in a peer-reviewed study published in the Astrophysical Journal. Official Hubble imagery released by NASA, ESA, and STScI includes scale bars and compass overlays confirming the disk’s physical extent.
Deeper wavelengths, same story
Scattered starlight only traces the disk’s upper surface layers, so a natural question is whether the lopsidedness goes all the way through. Independent millimeter-wavelength observations with the Submillimeter Array (SMA) and the NOEMA interferometer addressed that by probing thermal emission from cooler dust grains buried in the disk’s midplane.
The result: a north-south brightness difference reported as up to roughly 50 percent, confirming that the asymmetry is not a trick of viewing angle or surface scattering. The same data revealed signatures consistent with ring-like and cavity-like radial structures, suggesting that material inside the disk is being sculpted into distinct zones rather than spread out uniformly.
Taken together, the optical and millimeter observations paint a consistent picture: IRAS 23077+6707 is not just record-breakingly large but structurally unlike the relatively tidy disks seen around most other young stars.
Big questions still open
The most pressing mystery is what drives the disk’s stark lopsidedness. One leading hypothesis points to turbulence amplified by magnetic fields through a mechanism called magneto-rotational instability, which could trap dust unevenly across the disk. The edge-on viewing angle might exaggerate the apparent contrast, but the millimeter data, which peer through the dust layer, still detect the same imbalance, arguing against a purely geometric explanation.
No detailed spectroscopic study has yet nailed down the central star’s precise age, mass, or variability. Current estimates rely on survey-level photometry and spectral energy distribution modeling. Without tighter constraints on the star itself, it is hard to say whether the disk’s disorder reflects a specific evolutionary phase or something genuinely unusual about this system.
The ring and cavity structures hinted at in the millimeter data are tantalizing because they resemble gaps carved by orbiting protoplanets in other disks, such as the famous HL Tau system imaged by ALMA. But no direct detection of a forming planet has been reported here, and alternative explanations, including gravitational instabilities within the disk or interactions with surrounding cloud material, remain on the table.
Why a messy disk matters for planet formation
Most textbook illustrations of planet formation show smooth, symmetric disks where dust settles into neat rings and gradually clumps into worlds. IRAS 23077+6707 is a reminder that nature does not always cooperate with the diagrams.
If planets can form inside a structure this asymmetric, their orbits, compositions, and spacing could differ sharply from anything in our solar system or in the well-studied disks that have shaped current models. The system offers a natural laboratory for testing how far the planet-formation process can be pushed before it breaks down, or whether disorder might actually help certain kinds of worlds come together.
As of mid-2026, Berghea’s team and other groups are preparing proposals for polarized observations with the Atacama Large Millimeter Array (ALMA) that could map magnetic field orientations across the filaments, testing whether magnetically driven turbulence is the engine behind the asymmetry. For now, Dracula’s Chivito stands as the most extreme example astronomers have found of how disordered the planet-building process can get, and a signal that the universe’s construction sites are far stranger than the textbooks suggest.
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*This article was researched with the help of AI, with human editors creating the final content.
