JWST finds a barred spiral galaxy candidate 1.1 billion years after the Big Bang

A galaxy seen about 1.1 billion years after the Big Bang appears to have a stellar bar reaching 4.5 kiloparsecs from its centre, close to the Milky Way’s, though the bar is identified from images and still needs velocity measurements to confirm it.

Peer reviewed · Single galaxy · Imaging plus spectroscopy

Astronomers using the James Webb Space Telescope (JWST) report a galaxy with a central bar and spiral arms whose light left it when the universe was about 1.1 billion years old, roughly 8% of its present age. The team, led by Xiaohan Wang of Tsinghua University and Fengwu Sun of Westlake University, calls M1149-BSG-z5 the highest-redshift barred galaxy candidate to date. Bars were expected to be rare this early, because young disks were thought too turbulent to grow them. The catch: this bar is identified from its shape alone.

Evidence at a glance

Is this a big deal?

A solid step, not a revolution. It is one object, not a census. If confirmed, it beats the earliest bar-like structure on the authors’ list by about 230 million years, and well-measured bars by about 650 million.

What scientists found

A bar is a straight band of stars across a galaxy’s centre. About 60% of nearby disk galaxies have one, the paper notes, including the Milky Way. Bars funnel gas inwards, and they need a fairly calm disk to form, so their first appearance dates when disks settled.

M1149-BSG-z5 sits at redshift z = 5.1015 ± 0.0002. Using the paper’s cosmology, SciQuest calculates that the universe was about 1.15 billion years old then, counting from the Big Bang; the light has travelled about 12.7 billion years to reach us. It holds about 28 billion Suns’ worth of stars, roughly half the Milky Way’s total, and makes about 144 solar masses of new stars a year, nearly 90 times the Milky Way’s rate.

How they found it

The team spotted the galaxy by eye in Webb images beside the galaxy cluster MACS J1149+2223, then combined 16 Webb filters with three from Hubble. At 6.8 arcminutes from the cluster centre, lensing should be negligible, the authors say, so its shape is not stretched.

To test for a bar, they traced the galaxy’s light with nested ellipses, much like contour lines on a hiking map, though these trace brightness rather than height. Across a bar, the ellipses stretch at a fixed angle, then turn rounder and twist where the disk takes over. In red light, which tracks older stars, elongation peaks at 0.47 at 4.50 kpc, then drops to about 0.2 with a 20-degree twist. Subtracting a smooth bulge-plus-disk model left a bar and spiral arms. A NIRSpec spectrum fixed the redshift and revealed an active black hole.

For scale, 4.5 kpc is about 14,700 light-years. The Milky Way’s bar has a half-length of 5.0 ± 0.2 kpc in one widely used star-count model, so this young galaxy’s bar is about nine-tenths as long.

Why it matters to you

Nothing changes in daily life. This is about origins: bars like the one in your home galaxy may have formed within about a billion years of the Big Bang. See where Earth is in the Milky Way.

What the evidence does not show

A bar is a set of stars on elongated orbits; images show only its shape. The authors write: “Although spatially resolved kinematics are required for dynamical confirmation, the current photometric evidence favors the presence of a bar.” At this distance, a line of star-forming clumps could mimic one.

The size is uncertain too. In ultraviolet light the feature measures 2.1 kpc, and the authors warn that the outer disk and image blurring may stretch the 4.5 kpc figure. Mass and star formation rate come from model fits.

How this fits what we already knew

Hubble found bars in only about 10% of disk galaxies at z ≈ 1. Guo and colleagues (2023) measured six bars at z ≈ 1.1–2.3, with half-lengths of 2.9–4.3 kpc. Le Conte and colleagues (2024) found bars in about 14–18% of disk galaxies at z = 1–3, about twice the Hubble-based rate. Costantin and colleagues (2023) reported CEERS-2112, a barred spiral at a photometric redshift of about 3.

The new paper lists well-developed bars up to z = 3.5 and bar-like structures at z = 4.06 to 4.41. M1149-BSG-z5 also stands out for its long bar, its bright central bulge and its crowded setting: 11 neighbours share nearly its redshift.

Outside views

SciQuest found no comment from an astronomer outside the team as of 28 October 2026, 09:30 UTC, and has not interviewed one. Of the earlier studies above, Costantin et al. shares no author with the new paper; Guo et al. and Le Conte et al. share one each.

How other headlines framed it

All coverage found was of the June preprint. Phys.org called it the most distant barred galaxy known, dropping “candidate”. The Daily Galaxy led with its early age. Futura-Sciences asked whether it challenges cosmology. Hi-Tech Mail.ru stressed how early it matured. The paper’s claim is narrower: bar-forming disks arose earlier than expected.

What happens next

The authors call for velocity maps from ALMA or NIRSpec to test whether stars and gas move as a bar predicts. They float two origins: a tug from a small companion 21.2 kpc away, or instability in a gas-rich disk. Motion data can separate them.

In one sentence

Webb has found what looks like a Milky Way-sized bar in a galaxy seen 1.1 billion years after the Big Bang, the earliest such candidate yet, but only a velocity map can confirm it.

Read next

• Where is Earth in the Milky Way?
• Two faint galaxies found near one of the most pristine gas clouds known
• Milky Way’s disk settled in two stages, Gaia star ages suggest, the calm-disk story from inside our own galaxy.

Sources and disclosure

1. Wang, X., Sun, F., Asada, Y., et al. “A Massive Barred Spiral Galaxy at z = 5.102 Discovered by JWST.” The Astrophysical Journal 1011:54, published online 27 October 2026. doi:10.3847/1538-4357/aea414. Preprint arXiv:2606.25022.
2. Costantin, L., et al. “A Milky Way-like barred spiral galaxy at a redshift of 3.” Nature 623, 499–501 (2023). doi:10.1038/s41586-023-06636-x.
3. Guo, Y., Jogee, S., et al. “First Look at z > 1 Bars in the Rest-frame Near-infrared with JWST Early CEERS Imaging.” ApJ Letters 945, L10 (2023). doi:10.3847/2041-8213/acacfb.
4. Le Conte, Z. A., et al. “A JWST investigation into the bar fraction at redshifts 1 ≤ z ≤ 3.” MNRAS 530, 1984–2000 (2024). doi:10.1093/mnras/stae921.
5. Wegg, C., Gerhard, O., Portail, M. “The structure of the Milky Way’s bar outside the bulge.” MNRAS 450, 4050–4069 (2015). doi:10.1093/mnras/stv745.
6. Licquia, T. C., Newman, J. A. “Improved Estimates of the Milky Way’s Stellar Mass and Star Formation Rate.” ApJ 806, 96 (2015). doi:10.1088/0004-637X/806/1/96.

Disclosure: This article was drafted with AI assistance and checked against the sources above, including the full open-access paper. Calculations by SciQuest: cosmic age at z = 5.1015 ≈ 1.15 billion years and light-travel time ≈ 12.7 billion years for a flat universe with H₀ = 67.66 km/s/Mpc and Ω_m = 0.31 (the paper’s choice); 10^10.45 ≈ 2.8 × 10¹⁰ solar masses, about 0.46 of the Milky Way’s 6.1 × 10¹⁰; 144 ÷ 1.65 ≈ 87; 4.5 kpc × 3,262 ≈ 14,700 light-years; 4.5 ÷ 5.0 = 0.9. The two Milky Way comparisons use different initial-mass assumptions, so treat them as approximate. The paper reports support from Westlake University, the National Natural Science Foundation of China, NASA, JSPS, the Israel Science Foundation and Spanish and Andalusian research agencies; SciQuest has no conflicts to declare. The graphic is a SciQuest original drawn from the cited values. Spotted an error? See our corrections policy.