Sunday, November 01, 2026

Ghostly Cat’s Head Nebula Lurks Within Sight of NASA’s Hubble, Webb

NASA’s Hubble Space Telescope shows an opaque dust pillar edged by a luminous rim of gas. Surrounding blue regions include emission from ionized gas and scattered starlight. The cat’s glowing red eye may indicate a young star embedded in the dust. Credit Image: NASA, ESA, STScI; Image Processing: Joseph DePasquale (STScI)

NASA’s James Webb Space Telescope’s near-infrared view reveals detailed structures in the pillar and many stars, as well as some background galaxies. The glowing yellow eye may be a young star embedded in dust. Credit Image: NASA, ESA, CSA, STScI; Image Processing: Joseph DePasquale (STScI)

NASA’s James Webb Space Telescope’s mid-infrared view reveals intricate structures within the nebula, traced by the emission from warm dust and carbon-based molecules excited by starlight. Credit Image: NASA, ESA, CSA, STScI; Image Processing: Joseph DePasquale (STScI))

This visualization explores imagery from NASA’s Hubble and James Webb Space Telescopes of the Cat’s Head Nebula, a relatively small, dusty filament containing forming stars located within the massive Carina Nebula. Credit Producer: Gregory Bacon (STScI); Visualization: Leah Hustak (STScI), Christian Nieves (STScI), Alyssa Pagan (STScI), Joseph DePasquale (STScI); Script Writer: Frank Summers (STScI); Audio: Danielle Kirshenblat (STScI); Narration: Frank Summers (STScI); Acknowledgment: University of Minnesota, NOAO, AURA, NSF, DSS, Nathan Smith

This tour glides through imagery from NASA’s Hubble and James Webb Space Telescopes of the Cat’s Head Nebula. The dust filament broadly remains the same in shape across the different wavelengths of light, but each view contains different details. Credit Producer: Gregory Bacon (STScI), Frank Summers (STScI); Visualization: Leah Hustak (STScI), Christian Nieves (STScI), Alyssa Pagan (STScI), Joseph DePasquale (STScI)



Like a spectral form rising out of a cold mist, NASA’s Hubble and James Webb Space Telescopes have captured a hauntingly dynamic star-forming scene. It lies within the vast Carina Nebula, a diffuse star-forming region located about 7,500 light-years away from Earth. The small, select area both telescopes observed is nicknamed the Cat’s Head Nebula because of its resemblance to a cat sitting with its back toward the viewer. The “head” of the cat is turned to the right, revealing a glowing eye.

Though the Cat’s Head Nebula is a temporary scene that will eventually disperse as stars form and evolve over time, the region is packed with information. Hubble and Webb’s complementary views of the Cat’s Head Nebula are helping astronomers learn more about the elusive, chaotic, and complex process known as star formation.

The distinctive “cat’s head” shape of the nebula was likely sculpted over time by the intense ultraviolet radiation and winds from massive stars in the Carina Nebula. As this stellar feedback erodes the surrounding gas and dust, denser material within the feline-shaped pillar resists erosion, at least for now.

Hubble’s visible-light view reveals an opaque, dark brown pillar of dust. The cat’s glowing red eye may indicate a young star that is still partially embedded in dust. A ridge of hazy yellow seems to follow the edge of the filament’s right side. This bright rim is consistent with gas illuminated and ionized by ultraviolet radiation from nearby massive stars, potentially driving a process known as photoevaporation.

The diffuse material surrounding the pillar glows blue and cyan above, shifting to yellow, orange, and red toward the bottom. Hubble’s filters capture light emitted by oxygen, hydrogen, and sulfur, along with starlight scattered by dust. These color variations reveal a complex mix of excited gas, dust, and stellar illumination.

Piercing Through Dust’s Darkness

Webb’s near- and mid-infrared images each offer different pieces of information to help create a more well-rounded understanding of the Cat’s Head Nebula. While the nebula’s overall structure is similar to the visible-light Hubble image, the filament becomes more transparent, and its complex surface structure becomes discernable in near-infrared light seen by Webb. On the cat’s left are ghostly wisps of dust and gas, delicate structures exposed to radiation from nearby massive stars.

Webb’s near-infrared view reveals a dense scattering of stars, shown in blue and yellow. Even in infrared light, some stars are still enshrouded in dust to various degrees. The cat’s eye remains conspicuous. The telescope’s high-resolution imagery even shows faint background galaxies, offering a partial view through our Milky Way galaxy and beyond.

In mid-infrared light, emission from warm dust and carbon-based molecules excited by starlight outlines intricate structures within the nebula. Changes in local conditions and compositions lead to variations in color and brightness. Delicate globules and strands to the pillar’s left are particularly evident in this mid-infrared view.

To the right of the pillar, a bright light source is shown as yellow in the mid-infrared image. Likely an infant star embedded in dust, it lies against reddish emission from surrounding material. A narrow filament appears to cross the source, although the image alone cannot establish whether the two are physically related.

The Hubble Space Telescope has been operating for more than three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.

The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).




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Last Updated: Oct 29, 2026
Editor: Andrea Gianopoulos
Location:
NASA Goddard Space Flight Center

Contact Media:

Claire Andreoli
NASA’s Goddard Space Flight Center
Greenbelt, Maryland

claire.andreoli@nasa.gov

Abigail Major, Christine Pulliam
Space Telescope Science Institute
Baltimore, Maryland



What Lurks Within the Shadows of Betelgeuse?


Betegeuse's Haunted Atmosphere
This artist’s illustration shows the smaller, hotter companion star Siwarha creating a wake-like disruption in Betelgeuse’s outer atmosphere as it orbits directly through it. The shape of Betelgeuse itself becomes slightly oblong as a result of Siwarha's perturbations. Credit: NSF/AUI/NSF NRAO/M. Weiss



New Radio Images Reveal Disturbances from Mysterious Companion

The well-known star Betelgeuse has a mysterious houseguest — and it’s shaking the rafters, rattling the pipes, and slamming the cupboards. (Metaphorically speaking.) It’s causing enough subtle atmospheric disturbance that it might as well be making ghost noises. Who’s to blame? New data suggests that its recently discovered companion star, Siwarha, is the one doing the haunting.

Betelgeuse, the bright red supergiant marking the shoulder of Orion, has long captivated astronomers and skywatchers alike — never more so than in late 2019 and early 2020, when it dramatically dimmed to its faintest in more than a century of record-keeping. Now, a new study using the U.S. National Science Foundation’s Karl G. Jansky Very Large Array (NSF VLA) and the Atacama Large Millimeter/submillimeter Array (ALMA) shows that the star’s extended atmosphere has largely recovered from that episode — and the same data reveal compelling new evidence that Betelgeuse’s atmosphere is being actively perturbed by the aforementioned close-in stellar companion.

The results, led by Dr. Lynn D. Matthews, Principal Research Scientist and Assistant Director at MIT Haystack Observatory, along with colleagues from the Center for Astrophysics | Harvard & Smithsonian, the University of Manchester, and the European Southern Observatory, are based on observations at seven radio frequencies — from 22 GHz to 485 GHz — collected between 2021 and 2026. Because radio waves of different frequencies probe different depths in a star’s atmosphere, the combined NSF VLA and ALMA data let the team build a layer-by-layer picture of Betelgeuse’s atmosphere, from just above its visible surface out to several times the star’s radius.

“It was the combination of the incredible data from the NSF VLA and ALMA that gave us a convincing result here,” said Matthews. “The fact that we can use these facilities to actually resolve the disks of nearby stars is amazing.”

A Star Bouncing Back

In 2019, months before the Great Dimming (when Betelgeuse ejected a billion tons of solar material, partially blocking our view), a study led by Matthews had found that Betelgeuse’s atmosphere at radio wavelengths was unusually cool — a sign, the researchers proposed, that a shock wave triggered by convection deep in the star had disturbed the gas in its outer layers, setting the stage for the massive dust-forming outburst that followed. The new observations show that the brightness temperature of the star’s atmosphere at those same wavelengths has since climbed back to more typical levels. The star’s gas now measures around 3,500 Kelvin (comparable to Betelgeuse’s own surface temperature) near a radius of about 2.7 times the star’s own size.

The current team also confirmed a long-suspected “temperature minimum” in Betelgeuse’s atmosphere — a cool layer sandwiched between the star’s visible surface and the chromosphere above. Their highest-frequency ALMA measurements, reaching closer to the star’s surface than ever before, found gas temperatures dropping to roughly 2,200 Kelvin, over 1,000 degrees cooler than the photosphere itself. That chilly layer coincides with the so-called “MOLsphere,” a shell of molecular gas long inferred from infrared observations but rarely probed so directly at radio wavelengths.

Fingerprints of a Hidden Companion

Perhaps the most striking result concerns Betelgeuse’s recently identified companion star, Siwarha, whose existence was proposed in 2024 to explain the star’s mysterious 2,100-day brightness cycle and has since been supported by direct imaging and spectroscopic studies. Since Betelgeuse means “the hand of al-Jawza” in Arabic, the companion star was dubbed Siwarha, meaning “her bracelet.”

Siwarha is thought to orbit deep within Betelgeuse’s extended atmosphere, at a distance of only about twice the giant star’s radius. As Matthews explained, “This companion is orbiting so close to the star that it actually passes through its extended atmosphere.” Like a jet boat tearing through a lake, it’s likely leaving a wake in its path as the smaller star rips through the atmosphere. And as the new spatially resolved observations of Betelgeuse show, Siwarha’s presence is producing observable effects.

Although Siwarha itself is likely far too faint to detect directly at radio wavelengths — the team calculated it would be tens to hundreds of times too faint to see in their observations — its gravitational and physical presence appears to leave a mark on its giant host. By measuring the subtle egg-like shape (“ellipticity”) of Betelgeuse’s radio-emitting atmosphere across multiple epochs, the researchers found that the star becomes noticeably more elongated near the times when the companion is expected to be at its greatest apparent separation from Betelgeuse, and rounder when the companion is expected to be passing in front of or behind the star.

It’s a bit like watching ripples on a pond and being able to infer that something is moving just beneath the surface. Researchers can’t see the companion directly at radio wavelengths, but they can see its influence on the shape of Betelgeuse’s atmosphere as it moves along its orbit

Looking Ahead

The team notes that additional observations spanning a fuller range of the companion’s orbit — particularly at frequencies not yet well sampled — will be needed to confirm and refine these findings. Future observatories such as the Next Generation Very Large Array, currently in development, are expected to make such studies far more routine, offering an even sharper view of how red supergiant stars like Betelgeuse shed material and evolve in the final stages of their lives — and how the pull of a nearby companion might shape that process. The paper, “New Spatially Resolved Observations of Betelgeuse from the VLA and ALMA: Evidence for Atmospheric Perturbations from a Close Companion,” has been published in The Astronomical Journal.




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About the NSF NRAO

The NSF National Radio Astronomy Observatory (NSF NRAO) is a facility of the U.S. National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

About ALMA

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Southern Observatory (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science and Technology Council (NSTC) in Taiwan and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.