Everywhere we look, our Universe is filled with luminous matter.
The “red and dead” galaxy NGC 1277 is located inside the Perseus cluster. While other galaxies contain a mix of red and blue stars, this galaxy hasn’t formed new stars in about 10 billion years. Closer foreground objects like stars, as well as more distant galaxies, are all omnipresent in this image.
Galaxies, powered by stars, are scattered throughout the cosmos.
The galaxies that make up the Pandora Cluster, Abell 2744, are present within the cluster’s three distinct, easily visually identifiable components, while the remaining background sources are scattered throughout the Universe, many of which originate from the first billion years of cosmic history. This field of view is now known to contain many of the first galaxies ever discovered, as well as the youngest proto-cluster of galaxies ever discovered to date: just 650 million years after the Big Bang.
Further away, they are bluer, smaller and less evolved.
Galaxies comparable to today’s Milky Way are numerous, but younger galaxies that resemble the Milky Way are inherently smaller, bluer, more chaotic, and more gas-rich in general than the galaxies we see today. For early galaxies, this effect goes to the extreme. For as long as we have seen, galaxies have obeyed these rules.
Even at the limits of our instruments, galaxies still abound.
This tiny fraction of the JADES survey area, taken with JWST’s NIRCam instrument, details relatively close galaxies, galaxies at intermediate distances that appear clustered together, and even ultra-distant galaxies that may interact or form stars, despite their faint nature and red appearance. We are only beginning to probe the full richness of the cosmos with JWST.
There is no view deeper than JADES: the JWST Advanced Deep Extragalactic Survey.
This image shows the study region of the JWST Advanced Deep Extragalactic Survey (JADES). This area includes and contains Hubble’s extreme deep field and reveals new galaxies at record distances that Hubble could not see. Colors in JWST images are not “true colors”, but rather are assigned based on a variety of choices. This image, released in December 2022, has since been supplemented by follow-up observations in the same region of space, with spectroscopic observations needed to determine the distance to these galaxies.
With new spectroscopic data, the cosmic distance record has fallen again.
This image shows the spectrum, or intensity versus wavelength, of the distant galaxy JADES-GS-z14-0, as acquired with JWST’s NIRSpec instrument. The Lyman breakup function tells us that the galaxy is at a redshift of z=14.32, which corresponds to an age of the Universe at that time of only 285 million years.
JADES-GS-z14-0 is now the most distant galaxy ever discovered: only 285 million years after the Big Bang.
If we plot the cosmic distance record over time, it’s clear that there have been many big leaps: in the 1960s, in the late 1990s, and now again in the 2020s, during the JWST era. Even if uncertainties remain in cosmology, this new record galaxy should appear between 270 and 305 million years after the Big Bang.
Here are the 5 big lessons that we have already learned from its discovery.
Presented in the context of the JWST JADES field, the JADEs-GS-z14-0 galaxy is completely ordinary, but has nevertheless just broken the cosmic distance record again, becoming the first galaxy ever discovered when the Universe was less than 300 million years: just 2.1% of its current age.
1.) Not all early galaxies are compact.
Among the most distant galaxies, GN-z11 and GHZ2 are among the brightest, while remaining remarkably compact. JADES-GS-z14-1 is more typical: fainter but still very compact, while JADES-GS-z14-0 is more confusing: bright and extended, suggesting a physical size of around 1,700 light years at its distance amazing.
Although (second place) JADES-GS-z14-1 is spotty, its more distant sibling already spans 1,700 light years.
The galaxy JADES-GS-z14-0, alongside a much closer and unrelated rogue galaxy that lies in the exact same line of sight. Its extended nature is clearly visible even in this enlarged NIRCam image of the two galaxies.
2.) Not all ultra-distant candidate galaxies are right.
Before JWST, there were about 40 known ultra-distant candidate galaxies, mainly from Hubble observations. Initial JWST results revealed many more ultra-distant candidate galaxies, but now 717 of them have been discovered within JADES’ 125 square arc-minute field of view alone. The night sky as a whole is more than a million times larger, indicating that there are at least hundreds of millions of these ultra-distant galaxies to discover. While some will survive spectroscopic monitoring, others will not. There is still a lot of scientific work to be done.
Some possible ultra-distant galaxies are simply dusty and inherently red, spectroscopy reveals.
While JADES-GS-z14-0 and JADES-GS-z14-1 (in red) were found to be real ultra-distant galaxies, many candidate galaxies (in blue) will turn out to be imposters at smaller distances . from us: just inherently red and/or dusty. The blue dot surrounded by a black circle was also examined by NIRSpec, which showed that it was not an ultra-distant galaxy at all.
3.) Some galaxies are “hidden” by closer intruders.
JADES-GS-z14-0, in the top box, is behind (and just to the right of) a closer, brighter, bluer galaxy. It was only thanks to the power of spectroscopy with incredible resolution, capable of separating the two sources, that the nature of the most distant object could be determined.
JADES-GS-z14-0 was only found by disentangling this galaxy from a closer galaxy along the same line of sight.
The highly advanced NIRSpec instrument aboard JWST can capture light from a very small region of space. By correctly pointing the telescope, the desired sources, JADES-GS-z14-0 and JADES-GS-z14-1 in this case, can be acquired separately, even from extremely close and partially overlapping sources.
4.) This new record holder is remarkably and astonishingly brilliant.
By superimposing on the same graph the spectra of the three most distant galaxies ever discovered, JADES-GS-z13-0 (the previous record holder), JADES-GS-z14-0 (the current record holder) and JADES -GS- z14-1 (recently discovered with JADES-GS-z14-0), we can compare the luminosities of these three galaxies. The farthest away is also the brightest by a factor of 4 or 5, which poses a headache for astronomers.
Five times brighter than the previous record holder (JADES-GS-z13-0), JADES-GS-z14-0 is even incredibly visible to MIRI eyes.
This four-panel spread shows four different views of the JADES-GS-z14-0 galaxy with MIRI photometric data. The fact that this galaxy has so many emissions at 7.7 microns suggests that neutral, heated hydrogen (Balmer beta) and doubly ionized oxygen are both present in high abundance.
5.) But this galaxy is extremely dust-poor.
While later discovered galaxies typically exhibit large amounts of dust, consistent with theories of dust production from supernova events, these two new record galaxies show evidence of dust produced only by AGB stars, and not by the supernova. It’s a mysterious surprise in the new data.
It’s almost as if no supernovae had occurred there.
The central region of the supernova remnant SN 1987A, first seen by JWST’s NIRCam instrument in 2023. The gas and dust features inside the remnant have been revealed in more detail by JWST than any which previous observatory, such as the collapse of the core. supernovae are incredible sites of cosmic dust production.
With JWST, the past of our Universe continues to be brought to light.
Even from this magnified view of the JADES field, it is very difficult to spot with the naked eye the most distant galaxy ever discovered, JADES-GS-z14-0. This animation shows its location with a green circle: overlapping with a brighter, bluer, closer galaxy.
Mostly Mute Monday tells an astronomical story in images, visuals and no more than 200 words.