Skip to content
Starts With A Bang

It’s real! JWST breaks Hubble’s all-time distance record!

Leaving Hubble in the dust, JWST has officially seen a galaxy from just 320 million years after the Big Bang: at just 2.3% its current age.
JADES JWST z 13
This annotated, rotated image of the JADES survey, the JWST Advanced Deep Extragalactic Survey, shows off the new cosmic record-holder for most distant galaxy: JADES-GS-z13-0, whose light comes to us from a redshift of z=13.2 and a time when the Universe was only 320 million years old. This galaxy appears about twice as large, in terms of angular diameter, as it would appear if it were half the distance away: a counterintuitive consequence of our expanding Universe.
Credit: NASA, ESA, CSA, M. Zamani (ESA/Webb); Science credits: Brant Robertson (UC Santa Cruz), S. Tacchella (Cambridge), E. Curtis-Lake (UOH), S. Carniani (Scuola Normale Superiore), JADES Collaboration; Annotation: E. Siegel
Key Takeaways
  • Although Hubble showed us the far reaches of the deep Universe as never before, it was fundamentally limited and couldn’t see beyond 400 million years after the Big Bang.
  • JWST was designed, in part, to surpass those limits, but in order to know which objects are truly the earliest, most distant ones, long observations with spectra were required.
  • At last, the first ultra-distant galaxies from the JADES survey have been revealed by JWST’s superior data, and the most distant one has smashed Hubble’s old record: the first of likely many new records.
Sign up for the Starts With a Bang newsletter
Travel the universe with Dr. Ethan Siegel as he answers the biggest questions of all

At last, JWST has shattered the record for most distant galaxy.

The viewing area of the JADES survey, along with the four most distant galaxies verified within this field-of-view. The three galaxies at z = 13.20, 12.63, and 11.58 are all more distant than the previous record-holder, GN-z11, which had been identified by Hubble and has now been spectroscopically confirmed by JWST to be at a redshift of z = 10.6. No doubt these records will themselves be broken, possibly with galaxy candidates that already exist within the same field-of-view.
Credit: NASA, ESA, CSA, M. Zamani (ESA/Webb), Leah Hustak (STScI); Science credits: Brant Robertson (UC Santa Cruz), S. Tacchella (Cambridge), E. Curtis-Lake (UOH), S. Carniani (Scuola Normale Superiore), JADES Collaboration

At 33 billion light-years away, JADES-GS-z13-0 is the farthest object ever seen.

unreachable
The light from any galaxy that was emitted after the start of the hot Big Bang, 13.8 billion years ago, would have reached us by today so long as it’s within about 46.1 billion light-years at present. But the light from the earliest, most distant galaxies will be blocked by intervening matter and redshifted by the expanding Universe. Both represent severe challenges to detection, which is why Hubble couldn’t see beyond about a redshift of 11, even under the most serendipitous circumstances. JWST has already broken that record.
(Credit: F. Summers, A. Pagan, L. Hustak, G. Bacon, Z. Levay, and L. Frattere (STScI))

Its light was emitted just 320 million years after the Big Bang.

reionization
This schematic diagram of the Universe’s history, highlighting reionization, was created before the JWST era began in 2022. Before stars or galaxies formed, the Universe was full of light-blocking, neutral atoms, and most of the Universe doesn’t become fully reionized until 550 million years afterward. However, we have since learned that the “dark ages” came to an end, as many sources of stellar and galactic lights came into existence and shone brightly, long before that mark: and likely within the first 100-200 million years, if not earlier.
Credit: S. G. Djorgovski et al., Caltech; Caltech Digital Media Center

We’re seeing back 13.5 billion years: to when the Universe was 2.3% its current age.

The probabilities of finding galaxies of a certain redshift/brightness combination within a particular volume of space, color-coded for likelihood. The earliest JWST galaxy candidates (at z > 10), some of which have now been verified, don’t pose as much of a problem for what should exist within our Universe versus what we’re finding as the large, bright, massive galaxies at more modest (10 > z > 6) redshifts.
(Credit: M. Boylan-Kolchin, MNRAS submitted, 2022)

This far outstrips anything Hubble could’ve done.

James Webb Hubble
Only because the most distant galaxy spotted by Hubble, GN-z11, is located in a region where the intergalactic medium is mostly reionized, was Hubble able to reveal it to us at the present time, breaking the prior record held by EGSY8p7. Other galaxies that are at this same distance but aren’t along a serendipitously greater-than-average line of sight as far as reionization goes can only be revealed at longer wavelengths, and by observatories such as JWST. At present, GN-z11 has been relegated to the 9th most distant galaxy known as of 2024: in the JWST era.
Credit: NASA, ESA, P. Oesch and B. Robertson (University of California, Santa Cruz), and A. Feild (STScI)

Hubble is warm, small, and limited in wavelength range.

Over the course of 50 days, with a total of over 2 million seconds of total observing time (the equivalent of 23 complete days), the Hubble eXtreme Deep Field (XDF) was constructed from a portion of the prior Hubble Ultra Deep Field image. Combining light from ultraviolet through visible light and out to Hubble’s near-infrared limit, the XDF represented humanity’s deepest view of the cosmos: a record that stood until it was broken by JWST. In the red box, where no galaxies are seen by Hubble, the JWST’s JADES survey revealed the most distant galaxy to date: JADES-GS-z13-0. Extrapolating beyond what we see to what we know and expect must exist, we infer a total of ~2 sextillion stars within the observable Universe.
Credit: NASA, ESA, G. Illingworth, D. Magee, and P. Oesch (University of California, Santa Cruz), R. Bouwens (Leiden University), and the HUDF09 Team; Annotations and stitching by E. Siegel

JWST overcomes all of these constraints, while including a superior spectrograph.

james webb vs. hubble
The JWST, now fully operational, has seven times the light-gathering power of Hubble and is able to see much farther into the infrared portion of the spectrum, revealing those galaxies existing even earlier than what Hubble could ever see, owing to its longer-wavelength capabilities and much lower operating temperatures. Compared with other near-IR and mid-IR observatories, JWST’s capabilities are a factor of 10-1000 better, enabling superior discoveries.
Credit: NASA/JWST Science Team; composite by E. Siegel

By breaking up light into its individual wavelengths, JWST sees both absorbed and transmitted light.

The spectra obtained by JADES and the JWST NIRSpec instrument for the four most distant galaxies found within JADES survey as of December, 2022. The Lyman break feature, robustly identified here for each of the four galaxies, determines the distance and redshift beyond a reasonable doubt, which made JADES-GS-z13-0 the cosmic record-holder for most distant galaxy until May of 2024.
Credit: JADES Collaboration, E. Curtis-Lake et al., preprint, 2022

Using both the NIRCam and NIRSpec instruments, it’s begun conducting the JADES survey.

This image shows the region of study of the JWST Advanced Deep Extragalactic Survey (JADES). This area includes and contains the Hubble eXtreme Deep Field and reveals new galaxies at record-breaking distances that Hubble could not see. The colors on JWST images are not “true color” but rather are assigned based on a variety of choices. This image, released in December of 2022, has since been augmented by follow-on observations within the same region of space, with spectroscopic observations required to determine the distance to these galaxies.
Credit: NASA, ESA, CSA, M. Zamani (ESA/Webb); Science credits: Brant Robertson (UC Santa Cruz), S. Tacchella (Cambridge), E. Curtis-Lake (UOH), S. Carniani (Scuola Normale Superiore), JADES Collaboration

JADES — the JWST Advanced Deep Extragalactic Survey — will ultimately combine hundreds of hours of observations.

The spectroscopic identification of the Lyman break signature, present and easily visible in all four ultra-distant, JWST-identified galaxies from the JADES deep field, confirms their redshift and distance. This observation gave us, at the time, the top three most distant galaxies of all, with spectroscopic confirmation. The Lyman break feature, normally resulting in an ultraviolet photon, can be seen well into the infrared from these galaxies owing to the redshifting of the light during its journey.
Credit: NASA, ESA, CSA, M. Zamani (ESA/Webb), Leah Hustak (STScI); Science credits: Brant Robertson (UC Santa Cruz), S. Tacchella (Cambridge), E. Curtis-Lake (UOH), S. Carniani (Scuola Normale Superiore), JADES Collaboration

Whenever faint, red galaxies show a critical “cutoff” in wavelength, their distance/redshift can be measured.

A combination of spectroscopy (top), likelihood comparisons with detailed simulations (middle), and photometry (bottom) have all been used to determine the distance to and properties of most distant galaxy JADES-GS-z13-0. Further analysis rules out other line possibilities, including carbon, oxygen, and a Balmer break, ensuring this galaxy really is sending light to us from a whopping 13.5 billion years ago.
(Credit: JADES Collaboration, E. Curtis-Lake et al., preprint, 2022)

At a redshift of 13.2 — meaning the observed light is 1320% longer than the emitted wavelength — JADES-GS-z13-0 breaks Hubble’s old record.

This illustration shows the spectrum from the most distant galaxy identified in JWST’s first deep-field image, along with the spectral lines that correspond to various elements and ions. The spectrum showcases the power of spectroscopy to reveal an incontrovertible distance and redshift for this object, and these techniques are being used to identify the most distant galaxies detectable by JWST.
(Credit: NASA, ESA, CSA, and STScI)

Three similar, almost-as-distant galaxies in the same field strengthen the observational case for this galaxy’s robustness.

The four most distant galaxies identified as part of JADES, thus far, include three that surpass the threshold for “most distant galaxy” previously set by Hubble. With no more than a quarter of the total JADES data taken thus far, this record will likely fall again, perhaps multiple times, over the coming months and years, but the unambiguous feature of the Lyman break can clearly be seen. The most distant, JADES-GS-z13-0, took the record from Hubble in December of 2022, and still holds it today. Although these are among the youngest galaxies ever discovered, their stellar populations are not pristine.
Credit: NASA, ESA, CSA, M. Zamani (ESA/Webb), Leah Hustak (STScI); Science credit: Brant Robertson (UC Santa Cruz), S. Tacchella (Cambridge), E. Curtis-Lake (UOH), S. Carniani (Scuola Normale Superiore), JADES Collaboration

JADES is specifically designed to take advantage of JWST’s instrument’s unique capabilities.

This is a simulated JWST/NIRCam mosaic that was generated using JAGUAR and the NIRCam image simulator Guitarra, at the expected depth of the JADES Deep program. In the beginning of 2022, scientists noted that in its first year of science operations, JWST may break many records that Hubble set over the course of its 32 year (and counting) lifetime, including records for most distant galaxy and most distant star. The former has just fallen.
(Credit: C. Williams et al., ApJ, 2018)

With more observing time, fainter and more distant galaxies will appear, smashing even this new record.

james webb hubble
This animation showcases a portion of the Hubble eXtreme Deep Field, with 23 days of cumulative data, and a simulated view of what scientists expected JWST might see when it viewed this region. This simulation predates JWST’s launch, and has since been spectacularly superseded by actual JWST data.
Credit: NASA/ESA and Hubble/HUDF team; JADES collaboration for the NIRCam simulation

Mostly Mute Monday tells an astronomical story in images, visuals, and no more than 200 words. Talk less; smile more.

Sign up for the Starts With a Bang newsletter
Travel the universe with Dr. Ethan Siegel as he answers the biggest questions of all

Related

Up Next