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JWST observations of a planetary nebula support jet-driven explosion of core-collapse supernova remnant RCW 103

This paper proposes that the core-collapse supernova remnant RCW 103 was shaped by two energetic, misaligned pairs of jets, as evidenced by its morphological similarity to the jet-driven planetary nebula PMR 1, thereby supporting the jittering-jets explosion mechanism.

Original authors: Aleksei Klimov (Technion, Israel), Noam Soker (Technion, Israel)

Published 2026-05-22

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CC BY 4.0

Original authors: Aleksei Klimov (Technion, Israel), Noam Soker (Technion, Israel)

Original paper licensed under CC BY 4.0 (http://creativecommons.org/licenses/by/4.0/). ✨ This is an AI-generated explanation of the paper below. It is not written or endorsed by the authors. For technical accuracy, refer to the original paper. Read full disclaimer

The Big Picture: A Cosmic Detective Story

Imagine two very different cosmic events: a Planetary Nebula (a dying star gently blowing off its outer layers, like a flower blooming) and a Supernova Remnant (the violent, messy explosion of a massive star). Usually, astronomers think these two things look nothing alike.

But in this paper, the authors, Aleksei Klimov and Noam Soker, act like cosmic detectives. They found a "smoking gun" that suggests these two very different explosions were actually shaped by the same invisible force: powerful jets of energy shooting out from the center.

The Clue: A New Telescope Photo

The story starts with a brand-new, incredibly sharp photo taken by the James Webb Space Telescope (JWST) of a planetary nebula called PMR 1.

The Analogy: Imagine looking at a piece of dough that has been spun around. Usually, you see a flat circle. But in this photo, the dough has two giant, fluffy "ears" sticking out on opposite sides, connected by a thin, faint tunnel in the middle.
The Discovery: The authors realized that these "ears" and the "tunnel" (which they call a pipe) are classic signs of two powerful jets of gas shooting out from the center, inflating the dough like a balloon.

The Mystery: The Case of RCW 103

Next, the authors looked at a much older, violent explosion called RCW 103. This is the leftover shell of a supernova.

The Problem: For years, astronomers have been puzzled by RCW 103. It has a weird shape that looks like two slices of pizza (or two wide wedges) with a faint gap between them. But, unlike the planetary nebula, it doesn't have obvious "ears."
The Old Theory: Some scientists thought maybe just one pair of jets made this shape, but the "ears" were too faint to see or had already blown away.

The "Aha!" Moment

The authors compared the new JWST photo of the planetary nebula (PMR 1) with the X-ray photos of the supernova (RCW 103).

The Match: When you look at the brightest parts of the planetary nebula (ignoring the faint outer edges), it looks exactly like the supernova remnant. Both look like two clumpy "pizza slices" separated by a faint gap.
The Twist: The authors realized that the planetary nebula has huge, obvious ears, while the supernova only has the faint "bases" of ears.
The Conclusion: The supernova did have ears, just like the planetary nebula. They were just so faint and spread out that we couldn't see them clearly before. The shape of the supernova is actually a "faded copy" of the planetary nebula's shape.

The Mechanism: The "Jittering Jets"

So, what made these shapes? The paper argues for a mechanism called Jittering-Jets Explosion Mechanism (JJEM).

The Analogy: Imagine a firehose that is shaking wildly. Instead of spraying water in one straight line, it sprays in two directions, then maybe shifts slightly and sprays in two other directions.
The Claim: The authors say that when the massive star exploded, the new neutron star at the center didn't just fire one pair of jets. It fired two pairs of energetic jets that were slightly misaligned (like two firehoses shaking in slightly different directions).
- One pair of jets made the "pizza slices."
- The other pair made the "ears" (which are now faint and hard to see).

Why This Matters

For a long time, there has been a fierce debate in the astronomy community about how massive stars explode.

Team A says it's a slow, gentle push from heat (neutrinos).
Team B (which includes these authors) says it's a violent kick from jets.

The authors argue that the specific "pizza slice" and "ear" shapes we see in RCW 103 are impossible to make with the "gentle push" theory. They can only be made by powerful, jet-driven explosions. Therefore, this study is a strong piece of evidence that jets are the primary way massive stars explode.

Summary

The Clue: A new photo of a dying star (PMR 1) shows a shape made by two pairs of jets.
The Match: An old explosion (RCW 103) has the exact same shape, just with the "ears" faded away.
The Verdict: The explosion was caused by two pairs of energetic jets shaking and firing from the center, supporting the "Jet-Driven" theory of supernovae.

Technical Summary: JWST Observations of a Planetary Nebula Support Jet-Driven Explosion of Core-Collapse Supernova Remnant RCW 103

Problem Statement
The primary explosion mechanism for core-collapse supernovae (CCSNe) remains a subject of intense debate within the astrophysical community. Two competing theories exist: the neutrino-driven (delayed neutrino) mechanism and the jittering-jets explosion mechanism (JJEM). While the neutrino-driven mechanism is widely studied, it struggles to explain the point-symmetric morphologies observed in many CCSN remnants (CCSNRs). Conversely, the JJEM, which posits that a newly born neutron star launches several to approximately twenty pairs of jets with varying orientations and energies, naturally accounts for these complex, non-axisymmetric structures. However, a definitive observational consensus is lacking. The specific morphology of the CCSNR RCW 103 presents a puzzle: it exhibits features consistent with jet shaping (such as arcs and sectors) but lacks the clearly defined "ears" (polar protrusions) typically associated with jet-driven planetary nebulae (PNe). Previous studies suggested a single pair of jets shaped RCW 103, but the absence of clear ears and the specific sector-like structure remained unexplained.

Methodology
The authors employ a qualitative morphological comparison approach, a method previously successful in classifying PNe and identifying jet-shaped features. The study involves:

JWST Analysis: Utilizing new, high-resolution infrared images of the planetary nebula PMR 1 (PN G272.8+01.0) obtained with the MIRI instrument (Filter F1280W). The authors systematically adjust contrast and intensity levels to isolate specific structural features, such as "ears," "pipes" (narrow connecting regions), and "sectors."
CCSNR Analysis: Re-analyzing Chandra X-ray data of the remnant RCW 103 (ObsIDs 123 and 970) and Spitzer IR data. Similar to the PN analysis, the authors manipulate intensity scales to reveal faint structures, shells, and sector boundaries that are not immediately apparent in standard visualizations.
Comparative Morphology: The core of the methodology is a direct visual and structural comparison between the bright regions of PN PMR 1 and the X-ray morphology of RCW 103 to identify shared jet-driven signatures.

Key Contributions and Results

Morphological Similarity between PMR 1 and RCW 103: The JWST images of PN PMR 1 reveal a structure consisting of two opposite, large "ears" connected by a narrow, faint "pipe." When the faintest regions are removed, the brightest regions of PMR 1 form two clumpy sectors resembling wide "pizza slices." The authors demonstrate that the X-ray morphology of RCW 103 exhibits a strikingly similar two-sector structure.
Identification of Two Jet Pairs: Unlike previous studies that attributed RCW 103's shape to a single jet pair, the authors identify two distinct shells (S1 and S2) in the X-ray data. They propose that these shells result from two energetic pairs of jets rather than one.
Resolution of the "Missing Ears" Puzzle: The study explains the lack of prominent ears in RCW 103 by comparing it to the fainter regions of PMR 1. The authors argue that RCW 103 likely possessed large, prominent ears similar to PMR 1, but these have since dispersed into the interstellar medium and are now too faint to be detected in current X-ray observations. Only the bases of two of the four expected ears (East and West) are visible as traces in the X-ray image.
Geometric Configuration: The analysis suggests that the two pairs of jets in RCW 103 are not perfectly opposite (180° apart) but have a small angular offset in three dimensions. This misalignment is consistent with the predictions of the JJEM, where jets are launched with varying orientations and energies.
Energy and Velocity Scaling: The authors note that while the absolute velocities and energies of SNRs and PNe differ by orders of magnitude (SNR velocities $\sim 10^5$ km/s vs. PN velocities $\sim 300$ km/s; SNR energies $\sim 10^{50}$ erg vs. PN energies $\sim 10^{45}$ erg), the relative ratios of jet velocity to shell velocity and jet energy to shell energy are comparable in both systems. This supports the physical plausibility of the jet-shaping mechanism across these different evolutionary stages.

Significance and Claims
The paper claims that the morphological similarity between the jet-shaped PN PMR 1 and the CCSNR RCW 103 provides robust evidence that two energetic pairs of jets shaped RCW 103. This finding supports the Jittering-Jets Explosion Mechanism (JJEM) as the primary explosion mechanism for CCSNe.

The authors assert that:

The point-symmetric, multi-sector morphology of RCW 103 cannot be explained by the neutrino-driven mechanism but is a natural outcome of the JJEM.
The "missing" ears in RCW 103 are a result of temporal evolution (dispersion) rather than a lack of jet formation, a conclusion bolstered by the JWST observation of PMR 1 where ears are visible but the bright sectors dominate the morphology when contrast is adjusted.
This study represents a significant step in resolving the dispute between explosion mechanisms, as jet-shaped morphologies (particularly point-symmetric structures) are currently the only robust property capable of distinguishing between the competing theories.

The paper concludes that RCW 103 began its evolution as a point-symmetric CCSNR shaped by multiple jet pairs, and that deeper X-ray observations may eventually reveal the dispersed ears, further confirming the JJEM framework.