QSO MUSEUM: A large atlas of cosmic structures surrounding high-redshift quasars

Figure 1. Nine of the targeted quasars (white circles) and the uncovered cosmic structures as seen in Lyman-alpha emission (blue-green). Each cut-out image is roughly 1 million light years in size. Credit: MPA/Jay Gonzalez Lobos, Fabrizio Arrigoni Battaia

Figure 2: Average surface brightness (top panel) and velocity dispersion (bottom panel) of the Lyman-alpha emission as a function of distance from each of the 120 targeted quasars. The curves are colour-coded according to the luminosity of each quasar. Credit: MPA/Jay Gonzalez Lobos

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Quasars are active supermassive black holes located at the centres of massive galaxies that emit energy levels that far exceed the binding energy of their host galaxies. This substantial amount of energy has the potential to impact the gas within and around the galaxies, thereby influencing their evolution. While the importance of this process is acknowledged, its details are still the subject of significant debate. An international team of researchers led by MPA scientists has now obtained observations of the most extensive sample of hydrogen structures surrounding quasars in the early universe to better understand this feedback process. The data reveal how the gas responds to the energy released by the supermassive black holes over distances of several hundred thousand light years, providing a new way to study the impact of quasars on galaxy evolution.

Quasar feedback plays a key role in shaping the evolution of the most massive galaxies in the universe. As the supermassive black hole at the centre of a galaxy accretes matter, it powers a quasar — a bright, energetic outburst that can blow powerful winds and emit radiation into the surrounding galaxy. This energy can either heat up or sweep away the gas that would otherwise form new stars, thereby effectively shutting down star formation. This explains why giant galaxies stop growing and become filled with older stars. However, in principle, a quasar is not only able to affect its host galaxy's interstellar medium (its local fuel reservoir), but also the surrounding intergalactic gas. This means that a quasar could have an impact also on the fresh fuel for future star formation in the galaxy, thereby accelerating the galaxy quenching. Despite these ideas have been extensively discussed, the details of this feedback process still need to be fully understood.

Since the 1980s, it has been proposed that the impact of quasar energy on the surrounding gas could be assessed by targeting one of the most important lines of the hydrogen atom: the Lyman-alpha line. In a hydrogen atom, the electron can occupy different energy levels, like steps on a ladder. This specific ultraviolet line is emitted when an electron drops from the second energy level to the first. Since hydrogen is the most abundant element in the universe, this transition is ubiquitous and results in such bright emission that it can be seen at distances of billions of light years, enabling us to study galaxies and their surrounding gas in the early universe. Novel wide-field spectrographs, in particular, have opened a new window on the Lyman-alpha emission surrounding quasars. They allow the detection of emitting gas at distances of several hundred thousand light years from their host galaxies with short exposure times (about one hour; see, for example, Highlights from November 2019, May 2022 and January 2025).

Thanks to this new instrumentation — specifically the integral-field spectrograph MUSE on the Very Large Telescope — an international team led by MPA scientists has surveyed the largest sample of quasars to date in order to study their surrounding Lyman-alpha emission. The observations revealed intricate structures enveloping these quasars during cosmic noon, an epoch corresponding to approximately 11.5 billion years ago (examples are shown in Figure 1). Importantly, the 120 targeted quasars cover two orders of magnitude in luminosity, enabling the team to explore the effects of different energy inputs.

The scientists discovered that the surface brightness of the Lyman-alpha emission — how bright the emission appears per unit angular area — depends on quasar luminosity. Brighter quasars are associated with brighter extended emission (see Figure 2, top panel). Similarly, brighter quasars are associated with more turbulent gas reservoirs within about 30 kpc (approximately 100,000 light years; see Figure 2, bottom panel). Both these trends are evidence of the impact of quasar feedback (radiation and winds) on their surroundings. The team is now quantifying these trends in detail. For example, they have found that the velocity dispersion on inner scales varies as a function of quasar luminosity, following a well-defined power law. These findings could be used to test quasar feedback models and how they couple with the gas. Future work will focus on targeting additional line emissions besides Lyman-alpha in order to further constrain the impact of quasars on the gas on such large scales, as well as the physical properties of the emitting gas (e.g. MPA Highlights July 2025).

 Source: Max Planck Institute for Astrophysics/Reasearch Highlghts

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Authors:

Jay González Lobos, Jay
PhD student
Tel: 2030
valegl@mpa-garching.mpg.de

Fabrizio Arrigoni Battaia
Scientific Staff
Tel: 2288
arrigoni@mpa-garching.mpg.de

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Original publication

Jay González Lobos, Fabrizio Arrigoni Battaia, Aura Obreja, Guinevere Kauffmann, Emanuele Paolo Farina, Tiago Costa

QSO MUSEUM III: the circumgalactic medium in Lyα emission around 120 z\sim3 quasars covering the SDSS parameter space. Witnessing the instantaneous AGN feedback on halo scales

Submitted to A&A

Source

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Duel of the Dual: The Mystery of a Quasar Pair

Hubble Space Telescope image of the binary quasar pair J0749+2255
Credit: NASA, ESA, Yu-Ching Chen (UIUC), Hsiang-Chih Hwang (IAS), Nadia Zakamska (JHU), Yue Shen (UIUC)

Figure 1: A map of the flux detected around the Hɑ and [NII] lines in the J0749+2255 system.
The two quasars are found in the central region, denoted with “NE” and “SW.” 

Credit: Adapted from Ishikawa et al. 2025

Title: VODKA-JWST: Synchronized Growth of Two Supermassive Black Holes in a Massive Gas Disk? A 3.8 kpc Separation Dual Quasar at Cosmic Noon with the NIRSpec Integral Field Unit

Authors: Yuzo Ishikawa et al.
First Author’s Institution: Johns Hopkins University and MIT Kavli Institute for Astrophysics and Space Research
Status: Published in ApJ

Binary supermassive black holes are an interesting phenomenon, with implications for galaxy evolution and gravitational wave observations. It is thought that these supermassive black hole pairs most often arise from galaxy mergers, during which gas accretion can spark active galactic nucleus activity. Today’s article analyzes JWST observations of one particular pair of quasars (a type of active galactic nucleus) with the lovely poetic name of J0749+2255. As shown in Figure 1, these quasars (observed at a redshift of z = 2.17) are quite close together, separated by only 12,300 light-years. They find that the southwest quasar is about three times brighter than its partner in the northeast, but the real interesting stuff is found in the spectral analysis.

Figure 2: Spectral observations of the two quasars, vertically offset for clarity. The blue and red curves represent JWST observations, with the gray lines representing observations from previous works with other telescopes. The JWST results shown here demonstrate the remarkable similarity between the two quasars. Adapted from Ishikawa et al. 2025

Seeing Double?

Figure 2 shows the spectra for the SW and NE quasars, and the first thing that is impossible to ignore is just how similar they are. There are some small differences; for example, the NE quasar is slightly redder than the SW quasar, and some emission lines have different shapes and are a smidge offset from one another. But the general similarity brings up the possibility that what we’re looking at isn’t two separate quasars, but rather one object that’s being gravitationally lensed! The small differences in the spectra could be consistent with a lensing scenario, as they could be explained by time delays in the lensing or foreground contamination. A major problem with this idea, however, is that no observations of this system have provided evidence for a lens: we have not seen the massive foreground object that would actually be causing the gravitational lensing. While it’s possible that the lens is just incredibly faint, there’s no smoking gun for lensing happening here.

Figure 3: Maps of Hɑ emission with the quasar contributions removed. Left panel shows the flux, middle shows the velocity dispersion, and right the radial velocity. The radial velocity measurements provide strong evidence for a disk with gas rotation and relatively little disturbance, which is not usually the case for merger environments. Credit: Ishikawa et al. 2025

Disk Gas Enters the Chat

The story becomes even more complicated when you look beyond the quasars, as JWST observations also detected diffuse emission from gas as shown in Figure 3. This gas is at the same redshift as the quasars, and can thus be associated with their host galaxy. And crucially, this gas doesn’t show any signs of lensing, such as the distinct arcs or symmetry you find in other lensed systems. This, coupled with the differences in the quasar spectra, suggests that this is not a lensed system, and that in fact we are looking at two different quasars.

But even within this model there are mysteries afoot! It’s generally thought that dual quasar systems are found in galaxy mergers, and there is some evidence that we’re seeing that here. The region labeled T1 in Figure 1 is one such piece of evidence, thought to be a tidal tail formed by gravitational disruptions during a merger event. It’s also generally thought that mergers provide a key way to trigger active galactic nucleus activity, where the two supermassive black holes of the merging galaxies become fed by the same gas reservoir. This could explain why the two quasars in J0749+2255 are so similar, as they may have undergone very similar accretion histories.

However, this story is complicated by the dynamics within the gas surrounding the quasars. As shown in the rightmost panel of Figure 3, the quasars are embedded in a gas disk that’s rotating, with one half of the gas being redshifted and the other half blue shifted. The quasars aren’t separated into these two regions, but are rather both found at the center of the disk. And the gas is showing none of the kinematic disturbance we would expect during a major merger, as the disk seems to be relatively stable. So maybe we’re not witnessing a merger in progress, but rather a disk galaxy that is playing host to two quasars! Based on simulations, one way this could happen is if a major merger takes place at an earlier time, and two black holes form from the resulting instabilities. This is another possible explanation for why the quasars are so similar.

Overall, this work points to the complicated nature of dual quasar systems. Is this one quasar being lensed or two different quasars? If they are distinct objects, are we witnessing a merger of galaxies, or did they both form in one galaxy? Future observations may be the key to answering these questions, but for now it remains a very interesting system.

Original astrobite edited by Hillary Andales

Source: American Astronomical Society/AAS-Nova

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About the author, Skylar Grayson:

Skylar Grayson is an astrophysics PhD candidate and NSF Graduate Research Fellow at Arizona State University. Her primary research focuses on active galactic nucleus feedback processes in cosmological simulations. She also works in astronomy education research, studying online learners in both undergraduate and free-choice environments. In her free time, Skylar keeps herself busy doing science communication on social media, playing drums and guitar, and crocheting!

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Editor’s Note: Astrobites is a graduate-student-run organization that digests astrophysical literature for undergraduate students. As part of the partnership between the AAS and astrobites, we occasionally repost astrobites content here at AAS Nova. We hope you enjoy this post from astrobites; the original can be viewed at astrobites.org.

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NASA’s Chandra Sees Surprisingly Strong Black Hole Jet at Cosmic “Noon”

A black hole has blasted out a surprisingly powerful jet in the distant universe, according to a study from NASA’s Chandra X-ray Observatory. X-ray: NASA/CXC/CfA/J. Maithil et al.; Illustration: NASA/CXC/SAO/M. Weiss; Image Processing: NASA/CXC/SAO/N. Wolk

black hole has blasted out a surprisingly powerful jet in the distant universe, according to a new study from NASA’s Chandra X-ray Observatory. This jet exists early enough in the cosmos that it is being illuminated by the leftover glow from the big bang itself.

Astronomers used Chandra and the Karl G. Jansky Very Large Array (VLA) to study this black hole and its jet at a period they call “cosmic noon,” which occurred about three billion years after the universe began. During this time most galaxies and supermassive black holes were growing faster than at any other time during the history of the universe.

The main graphic is an artist’s illustration showing material in a disk that is falling towards a supermassive black hole. A jet is blasting away from the black hole towards the upper right, as Chandra detected in the new study. The black hole is located 11.6 billion light-years from Earth when the cosmic microwave background (CMB), the leftover glow from the big bang, was much denser than it is now. As the electrons in the jets fly away from the black hole, they move through the sea of CMB radiation and collide with microwave photons. These collisions boost the energy of the photons up into the X-ray band (purple and white), allowing them to be detected by Chandra even at this great distance, which is shown in the inset.

Researchers, in fact, identified and then confirmed the existence of two different black holes with jets over 300,000 light-years long. The two black holes are 11.6 billion and 11.7 billion light-years away from Earth, respectively. Particles in one jet are moving at between 95% and 99% of the speed of light (called J1405+0415) and in the other at between 92% and 98% of the speed of light (J1610+1811). The jet from J1610+1811 is remarkably powerful, carrying roughly half as much energy as the intense light from hot gas orbiting the black hole.

The team was able to detect these jets despite their great distances and small separation from the bright, growing supermassive black holes — known as “quasars” — because of Chandra’s sharp X-ray vision, and because the CMB was much denser then than it is now, enhancing the energy boost described above.

When quasar jets approach the speed of light, Einstein’s theory of special relativity creates a dramatic brightening effect. Jets aimed toward Earth appear much brighter than those pointed away. The same brightness astronomers observe can come from vastly different combinations of speed and viewing angle. A jet racing at near-light speed but angled away from us can appear just as bright as a slower jet pointed directly at Earth.

The researchers developed a novel statistical method that finally cracked this challenge of separating effects of speed and of viewing angle. Their approach recognizes a fundamental bias: astronomers are more likely to discover jets pointed toward Earth simply because relativistic effects make them appear brightest. They incorporated this bias using a modified probability distribution, which accounts for how jets oriented at different angles are detected in surveys. Their method works by first using the physics of how jet particles scatter the CMB to determine the relationship between jet speed and viewing angle. Then, instead of assuming all angles are equally likely, they apply the relativistic selection effect: jets beamed toward us (smaller angles) are overrepresented in our catalogs. By running ten thousand simulations that match this biased distribution to their physical model, they could finally determine the most probable viewing angles: about 9 degrees for J1405+0415 and 11 degrees for J1610+1811.

These results were presented by Jaya Maithil (Center for Astrophysics | Harvard & Smithsonian) at the 246th meeting of the American Astronomical Society in Anchorage, AK, and are also being published in The Astrophysical Journal. A preprint is available here. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.

Source: NASA’s Chandra X-ray Observatory

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Visual Description

This release is supported by an artist’s illustration of a jet blasting away from a supermassive black hole.

The black hole sits near the center of the illustration. It resembles a black marble with a fine yellow outline. Surrounding the black hole is a swirling disk, resembling a dinner plate tilted to face our upper right. This disk comprises concentric rings of fiery swirls, dark orange near the outer edge, and bright yellow near the core.

Shooting out of the black hole are two streaky beams of silver and pale violet. One bright beam shoots up toward our upper right, and a second somewhat dimmer beam shoots in the opposite direction, down toward our lower left. These beams are encircled by long, fine, corkscrewing lines that resemble stretched springs.

This black hole is located 11.6 billion light-years from Earth, much earlier in the history of the universe. Near this black hole, the leftover glow from the big bang, known as the cosmic microwave background or CMB, is much denser than it is now. As the electrons in the jets blast away from the black hole, they move through the sea of CMB radiation. The electrons boost the energies of the CMB light into the X-ray band, allowing the jets to be detected by Chandra, even at this great distance.

Inset at our upper righthand corner is an X-ray image depicting this interaction. Here, a bright white circle is ringed with a band of glowing purple energy. The jet is the faint purple line shooting off that ring, aimed toward our upper right, with a blob of purple energy at its tip

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News Media Contact

Megan Watzke
Chandra X-ray Center
Cambridge, Mass.
617-496-7998
mwatzke@cfa.harvard.edu

Lane Figueroa
Marshall Space Flight Center, Huntsville, Alabama
256-544-0034
lane.e.figueroa@nasa.gov

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'Cosmic joust': astronomers observe pair of galaxies in deep-space battle

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ALMA image of the ‘cosmic joust’

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Artist’s impression of a ‘cosmic joust’

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Wide-field view of the region of the sky around a ‘cosmic joust’

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Videos

PR Video eso2509a
Astronomers observe pair of galaxies in deep-space battle | ESO News

PR Video eso2509b
Zooming into a pair of jousting galaxies

PR Video eso2509c
Animation of a pair of jousting galaxies

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Astronomers have witnessed for the first time a violent cosmic collision in which one galaxy pierces another with intense radiation. Their results, published today in Nature, show that this radiation dampens the wounded galaxy’s ability to form new stars. This new study combined observations from both the European Southern Observatory’s Very Large Telescope (ESO’s VLT) and the Atacama Large Millimeter/submillimeter Array (ALMA), revealing all the gory details of this galactic battle.

In the distant depths of the Universe, two galaxies are locked in a thrilling war. Over and over, they charge towards each other at speeds of 500 km/s on a violent collision course, only to land a glancing blow before retreating and winding up for another round. “We hence call this system the ‘cosmic joust’,” says study co-lead Pasquier Noterdaeme, a researcher at the Institut d'Astrophysique de Paris, France, and the French-Chilean Laboratory for Astronomy in Chile, drawing a comparison to the medieval sport. But these galactic knights aren’t exactly chivalrous, and one has a very unfair advantage: it uses a quasar to pierce its opponent with a spear of radiation.

Quasars are the bright cores of some distant galaxies that are powered by supermassive black holes, releasing huge amounts of radiation. Both quasars and galaxy mergers used to be far more common, appearing more frequently in the Universe’s first few billion years, so to observe them astronomers peer into the distant past with powerful telescopes. The light from this ‘cosmic joust’ has taken over 11 billion years to reach us, so we see it as it was when the Universe was only 18% of its current age.

“Here we see for the first time the effect of a quasar’s radiation directly on the internal structure of the gas in an otherwise regular galaxy,” explains study co-lead Sergei Balashev, who is a researcher at the Ioffe Institute in St Petersburg, Russia. The new observations indicate that radiation released by the quasar disrupts the clouds of gas and dust in the regular galaxy, leaving only the smallest, densest regions behind. These regions are likely too small to be capable of star formation, leaving the wounded galaxy with fewer stellar nurseries in a dramatic transformation..

But this galactic victim isn’t all that is being transformed. Balashev explains: “These mergers are thought to bring huge amounts of gas to supermassive black holes residing in galaxy centres.” In the cosmic joust, new reserves of fuel are brought within reach of the black hole powering the quasar. As the black hole feeds, the quasar can continue its damaging attack..

This study was conducted using ALMA and the X-shooter instrument on ESO’s VLT, both located in Chile’s Atacama Desert. ALMA’s high resolution helped the astronomers clearly distinguish the two merging galaxies, which are so close together they looked like a single object in previous observations. With X-shooter, researchers analysed the quasar’s light as it passed through the regular galaxy. This allowed the team to study how this galaxy suffered from the quasar’s radiation in this cosmic fight..

Observations with larger, more powerful telescopes could reveal more about collisions like this. As Noterdaeme says, a telescope like ESO’s Extremely Large Telescope “will certainly allow us to push forward a deeper study of this, and other systems, to better understand the evolution of quasars and their effect on host and nearby galaxies.”.

Source: ESO/News

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More information

This research was presented in a paper to appear in Nature titled “Quasar radiation transforms the gas in a merging companion galaxy.” (doi: 10.1038/s41586-025-08966-4)

The team is composed of S. Balashev (Ioffe Institute, St Petersburg, Russia), P. Noterdaeme (Institut d’Astrophysique de Paris, Paris, France [IAP] French-Chilean Laboratory for Astronomy [FCLA], Chile), N. Gupta (Inter-University Centre for Astronomy, Pune, India [IUCAA]), J.K. Krogager (Université Lyon I, Lyon, France FCLA), F. Combes (Collège de France, Paris, France), S. López (Universidad de Chile [UChile]), P. Petitjean (IAP), A. Omont (IAP), R. Srianand (IUCAA), and R. Cuellar (UChile).

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of 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.

The European Southern Observatory (ESO) enables scientists worldwide to discover the secrets of the Universe for the benefit of all. We design, build and operate world-class observatories on the ground — which astronomers use to tackle exciting questions and spread the fascination of astronomy — and promote international collaboration for astronomy. Established as an intergovernmental organisation in 1962, today ESO is supported by 16 Member States (Austria, Belgium, Czechia, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom), along with the host state of Chile and with Australia as a Strategic Partner. ESO’s headquarters and its visitor centre and planetarium, the ESO Supernova, are located close to Munich in Germany, while the Chilean Atacama Desert, a marvellous place with unique conditions to observe the sky, hosts our telescopes. ESO operates three observing sites: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its Very Large Telescope Interferometer, as well as survey telescopes such as VISTA. Also at Paranal ESO will host and operate the Cherenkov Telescope Array South, the world’s largest and most sensitive gamma-ray observatory. Together with international partners, ESO operates ALMA on Chajnantor, a facility that observes the skies in the millimetre and submillimetre range. At Cerro Armazones, near Paranal, we are building “the world’s biggest eye on the sky” — ESO’s Extremely Large Telescope. From our offices in Santiago, Chile we support our operations in the country and engage with Chilean partners and society.

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Contacts:

Pasquier Noterdaeme
Institut d'Astrophysique de Paris
Paris, France
Tel: +33 1 44 32 81 65
Email: noterdaeme@iap.fr

Sergei Balashev
Ioffe Institute
St Petersburg, Russia
Tel: +7 921 970 2553
Email: s.balashev@gmail.com

Bárbara Ferreira
ESO Media Manager
Garching bei München, Germany
Tel: +49 89 3200 6670
Cell: +49 151 241 664 00
,hr Email: press@eso.org

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Astronomers detect ancient lonely quasars with murky origins

This image, taken by NASA’s James Webb Space Telescope, shows an ancient quasar (circled in red) with fewer than expected neighboring galaxies (bright blobs), challenging physicists’ understanding of how the first quasars and supermassive black holes formed. Credit: Christina Eilers/EIGER team

The quasars appear to have few cosmic neighbors, raising questions about how they first emerged more than 13 billion years ago

A quasar is the extremely bright core of a galaxy that hosts an active supermassive black hole at its center. As the black hole draws in surrounding gas and dust, it blasts out an enormous amount of energy, making quasars some of the brightest objects in the universe. Quasars have been observed as early as a few hundred million years after the Big Bang, and it’s been a mystery as to how these objects could have grown so bright and massive in such a short amount of cosmic time..

Scientists have proposed that the earliest quasars sprang from overly dense regions of primordial matter, which would also have produced many smaller galaxies in the quasars’ environment. But in a new MIT-led study, astronomers observed some ancient quasars that appear to be surprisingly alone in the early universe.

The astronomers used NASA’s James Webb Space Telescope (JWST) to peer back in time, more than 13 billion years, to study the cosmic surroundings of five known ancient quasars. They found a surprising variety in their neighborhoods, or “quasar fields.” While some quasars reside in very crowded fields with more than 50 neighboring galaxies, as all models predict, the remaining quasars appear to drift in voids, with only a few stray galaxies in their vicinity.

These lonely quasars are challenging physicists’ understanding of how such luminous objects could have formed so early on in the universe, without a significant source of surrounding matter to fuel their black hole growth.

“Contrary to previous belief, we find on average, these quasars are not necessarily in those highest-density regions of the early universe. Some of them seem to be sitting in the middle of nowhere,” says Anna-Christina Eilers, assistant professor of physics at MIT. “It’s difficult to explain how these quasars could have grown so big if they appear to have nothing to feed from.”

There is a possibility that these quasars may not be as solitary as they appear, but are instead surrounded by galaxies that are heavily shrouded in dust and therefore hidden from view. Eilers and her colleagues hope to tune their observations to try and see through any such cosmic dust, in order to understand how quasars grew so big, so fast, in the early universe.

Eilers and her colleagues report their findings in a paper appearing today in the Astrophysical Journal. The MIT co-authors include postdocs Rohan Naidu and Minghao Yue; Robert Simcoe, the Francis Friedman Professor of Physics and director of MIT’s Kavli Institute for Astrophysics and Space Research; and collaborators from institutions including Leiden University, the University of California at Santa Barbara, ETH Zurich, and elsewhere.

Galactic neighbors

The five newly observed quasars are among the oldest quasars observed to date. More than 13 billion years old, the objects are thought to have formed between 600 to 700 million years after the Big Bang. The supermassive black holes powering the quasars are a billion times more massive than the sun, and more than a trillion times brighter. Due to their extreme luminosity, the light from each quasar is able to travel over the age of the universe, far enough to reach JWST’s highly sensitive detectors today.

“It’s just phenomenal that we now have a telescope that can capture light from 13 billion years ago in so much detail,” Eilers says. “For the first time, JWST enabled us to look at the environment of these quasars, where they grew up, and what their neighborhood was like.”

The team analyzed images of the five ancient quasars taken by JWST between August 2022 and June 2023. The observations of each quasar comprised multiple “mosaic” images, or partial views of the quasar’s field, which the team effectively stitched together to produce a complete picture of each quasar’s surrounding neighborhood.

The telescope also took measurements of light in multiple wavelengths across each quasar’s field, which the team then processed to determine whether a given object in the field was light from a neighboring galaxy, and how far a galaxy is from the much more luminous central quasar.

“We found that the only difference between these five quasars is that their environments look so different,” Eilers says. “For instance, one quasar has almost 50 galaxies around it, while another has just two. And both quasars are within the same size, volume, brightness, and time of the universe. That was really surprising to see.”

Growth spurts

The disparity in quasar fields introduces a kink in the standard picture of black hole growth and galaxy formation. According to physicists’ best understanding of how the first objects in the universe emerged, a cosmic web of dark matter should have set the course. Dark matter is an as-yet unknown form of matter that has no other interactions with its surroundings other than through gravity.

Shortly after the Big Bang, the early universe is thought to have formed filaments of dark matter that acted as a sort of gravitational road, attracting gas and dust along its tendrils. In overly dense regions of this web, matter would have accumulated to form more massive objects. And the brightest, most massive early objects, such as quasars, would have formed in the web’s highest-density regions, which would have also churned out many more, smaller galaxies.

“The cosmic web of dark matter is a solid prediction of our cosmological model of the Universe, and it can be described in detail using numerical simulations,” says co-author Elia Pizzati, a graduate student at Leiden University. “By comparing our observations to these simulations, we can determine where in the cosmic web quasars are located.”

Scientists estimate that quasars would have had to grow continuously with very high accretion rates in order to reach the extreme mass and luminosities at the times that astronomers have observed them, fewer than 1 billion years after the Big Bang.

“The main question we’re trying to answer is, how do these billion-solar-mass black holes form at a time when the universe is still really, really young? It’s still in its infancy,” Eilers says.

The team’s findings may raise more questions than answers. The “lonely” quasars appear to live in relatively empty regions of space. If physicists’ cosmological models are correct, these barren regions signify very little dark matter, or starting material for brewing up stars and galaxies. How, then, did extremely bright and massive quasars come to be?

“Our results show that there’s still a significant piece of the puzzle missing of how these supermassive black holes grow,” Eilers says. “If there’s not enough material around for some quasars to be able to grow continuously, that means there must be some other way that they can grow, that we have yet to figure out.”

This research was supported, in part, by the European Research Council.

By Jennifer Chu | MIT News

Source: Massachusetts Institute of Technology (MIT)

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DESI Looks 11 Billion Years Into the Past to Reveal Most Detailed View Ever of the Expanding Universe

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Artistic Composition of DESI Year-One Data Slice Above the Nicholas U. Mayall 4-meter Telescope

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DESI Year-One Data Slice

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DESI Year-One Data Slice (annotated)

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DESI Uses Distant Quasars to Map the Cosmic Web

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How Baryon Acoustic Oscillations Are Used to Measure the Expanding Universe

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DESI Year-One Data Slice with Cone

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The Dark Energy Spectroscopic Instrument Installed on the Nicholas U. Mayall 4-meter Telescope

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Videos

PR Video noirlab2408a

Cosmoview Episode 78: DESI Looks 11 Billion Years Into the Past to Reveal Most Detailed View Ever of the Expanding Universe

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Cosmoview Episodio 78: Revelan detallada panorámica de 11 mil millones de años hacia el pasado del Universo


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DESI Slice Fly-through


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DESI Slice Rotation


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Baryon Acoustic Oscillations Left Over From the Nascent Universe


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Nicholas U. Mayall 4-meter Telescope Interior


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Fulldome DESI Slice Fly-through


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SOS/Equirectangular DESI Slice Fly-through

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Using first-year data from the Dark Energy Spectroscopic Instrument Survey, astronomers have reported unprecedented measurements of dark energy and its effect on the expanding Universe

The Dark Energy Spectroscopic Instrument is conducting a five-year survey to create the largest 3D map of the Universe ever. Astronomers are now performing initial analysis of the survey’s first-year data. Using spectra of nearby galaxies and distant quasars, astronomers report that they have measured the expansion history of the Universe with the highest precision ever, providing an unprecedented look at the nature of dark energy and its effect on the Universe's large-scale structure.

Since beginning its survey of the sky in 2021 the Dark Energy Spectroscopic Instrument (DESI) has observed a new set of 5000 galaxies every 20 minutes, totalling more than 100,000 galaxies per night, in its quest to create the largest 3D map of the Universe ever. Using the survey’s first-year data, which contains the largest extragalactic spectroscopic sample ever collected, astronomers report that they have measured the Universe’s expansion history over the last 11 billion years with a precision better than 1%. These measurements confirm the basics of our best model of the Universe, while also uncovering some tantalizing areas to explore with more data.

DESI is an international science collaboration of more than 900 researchers from over 70 institutions around the world. DESI is managed by the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (LBNL) with primary funding from the Department’s Office of Science. The instrument is mounted on the U.S. National Science Foundation Nicholas U. Mayall 4-meter Telescope at Kitt Peak National Observatory, a Program of NSF NOIRLab.

To map the cosmos, DESI collects light from millions of galaxies across more than a third of the entire sky. By breaking down the light from each galaxy into its spectrum of colors, DESI can determine how much the light has been redshifted, or stretched to a longer wavelength, by the expansion of the Universe during the billions of years it traveled before reaching Earth. In general, the higher the redshift the further away the galaxy is.

Equipped with 5000 tiny robotic ‘eyes,’ DESI is able to perform this measurement at an unprecedented rate. In its first year alone DESI surpassed all previous surveys of its kind in terms of quantity and quality. With incredible depth and precision, DESI has brought new insight to one of the biggest mysteries in physics: dark energy — the unknown ingredient causing the expansion of our Universe to accelerate [1].

“The DESI instrument has transformed the Mayall Telescope into the world’s premier cosmic cartography machine,” says Pat McCarthy, Director of NOIRLab. “The DESI team has set a new standard for studies of large-scale structure in the Universe. These first-year data are only the beginning of DESI’s quest to unravel the expansion history of the Universe and they hint at the extraordinary science to come."

DESI’s first-year data have allowed astronomers to measure the expansion rate of the Universe out to 11 billion years in the past, when the Universe was only a quarter of its current age, using a feature of the large-scale structure of the Universe called Baryon Acoustic Oscillations (BAO).

BAO are the leftover imprint of pressure waves that permeated the early Universe when it was nothing but a hot, dense soup of subatomic particles. As the Universe expanded and cooled the waves stagnated, freezing the ripples in place and seeding future galaxies in the dense areas. This pattern, resembling the rippling surface of a pond after a handful of pebbles is tossed in, can be seen in DESI’s detailed map, which shows strands of galaxies clustered together, separated by voids where there are fewer objects.

At a certain distance, the BAO pattern becomes too faint to detect using typical galaxies. So instead astronomers look at the ‘shadow’ of the pattern as it’s backlit by extremely distant, bright galactic cores known as quasars. As the quasars’ light travels across the cosmos it gets absorbed by intergalactic clouds of gas, allowing astronomers to map the pockets of dense matter. To implement this technique, researchers used 450,000 quasars — the largest set ever collected for this type of study.

With DESI’s unique ability to map millions of objects both near and far, the BAO pattern can be used as a cosmic ruler. By mapping nearby galaxies and distant quasars, astronomers can measure the spread of the ripples across several periods of cosmic history to see how dark energy has stretched the scale over time.

“We’re incredibly proud of the data, which have produced world-leading cosmology results,” said Michael Levi, DESI director and LBNL scientist. “So far we’re seeing basic agreement with our best model of the Universe, but we’re also seeing some potentially interesting differences that could indicate dark energy is evolving with time.”

While the expansion history of the Universe may be more complex than previously imagined, confirmation of this must await the completion of the DESI project. By the end of its five-year survey DESI plans to map over 3 million quasars and 37 million galaxies. As more data are released, astronomers will further improve their results.

“This project is addressing some of the biggest questions in astronomy, like the nature of the mysterious dark energy that drives the expansion of the Universe,” says Chris Davis, NSF program director for NOIRLab. “The exceptional and continuing results yielded by the NSF Mayall telescope with DOE DESI will undoubtedly drive cosmology research for many years to come.”

“We are delighted to see cosmology results from DESI's first year of operations," said Gina Rameika, associate director for High Energy Physics at the Department of Energy. "DESI continues to amaze us with its stellar performance and how it is shaping our understanding of dark energy in the Universe."

Data from DESI’s survey will work harmoniously with future sky surveys conducted by Vera C. Rubin Observatory and the Nancy Grace Roman Space Telescope, with each instrument’s strength complementing the others. The DESI collaboration is currently investigating potential upgrades to the instrument and planning to expand their cosmological exploration into a second phase, DESI-II, as recommended in a recent report by the U.S. Particle Physics Project Prioritization Panel.

While the DESI year-one data are not yet publicly available, researchers can access the early data release as searchable databases of catalogs and spectra via the Astro Data Lab and SPARCL at the Community Science and Data Center, a Program of NSF NOIRLab.

Source: NSF’s National Optical-Infrared Astronomy Research Laboratory (NOIRLab)/News

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Notes

[1] As an organization, NOIRLab has committed decades of research to dark matter and dark energy measurements, with multiple NOIRLab-operated telescopes, including the Nicholas U. Mayall 4-meter Telescope, contributing to ground-breaking discoveries in these areas, one of which received the 2011 Nobel Prize in Physics

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More information

Researchers shared the analysis of their first year of collected data in several papers that will be posted today on the arXiv and in talks at the American Physical Society Meeting in the U.S. and the Rencontres de Moriond in Italy.

DESI is supported by the DOE Office of Science and by the National Energy Research Scientific Computing Center, a DOE Office of Science user facility. Additional support for DESI is provided by the U.S. National Science Foundation, the Science and Technology Facilities Council of the United Kingdom, the Gordon and Betty Moore Foundation, the Heising-Simons Foundation, the French Alternative Energies and Atomic Energy Commission (CEA), the National Council of Science and Technology of Mexico, the Ministry of Science and Innovation of Spain, and by the DESI member institutions.

The DESI collaboration is honored to be permitted to conduct scientific research on Iolkam Du’ag (Kitt Peak), a mountain with particular significance to the Tohono O’odham Nation.

NSF NOIRLab (U.S. National Science Foundation National Optical-Infrared Astronomy Research Laboratory), the U.S. center for ground-based optical-infrared astronomy, operates the International Gemini Observatory (a facility of NSF, NRC–Canada, ANID–Chile, MCTIC–Brazil, MINCyT–Argentina, and KASI–Republic of Korea), Kitt Peak National Observatory (KPNO), Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC), and Vera C. Rubin Observatory (operated in cooperation with the Department of Energy’s SLAC National Accelerator Laboratory). It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona. The astronomical community is honored to have the opportunity to conduct astronomical research on I’oligam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawai‘i, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence that these sites have to the Tohono O’odham Nation, to the Native Hawaiian community, and to the local communities in Chile, respectively.

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Links

• Read the DESI Y1 papers
• Visit the Dark Energy Spectroscopic Instrument webpage
• Access DESI Early-Release data
• Images of DESI
• Videos of DESI
• Images of Nicholas U. Mayall 4-meter telescope
• Videos of Nicholas U. Mayall 4-meter telescope
• Check out other NOIRLab Organization Releases
• Lawrence Berkeley National Laboratory press release

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Contacts

Arjun Dey
NSF NOIRLab
Email:arjun.dey@noirlab.edu

Nathalie Palanque-Delabrouille
Lawrence Berkeley National Laboratory
DESI Co-spokesperson
Email:npalanque-delabrouille@lbl.gov

Kyle Dawson
University of Utah
DESI Co-spokesperson
Email: kdawson@astro.utah.edu

Eric Linder
Lawrence Berkeley National Laboratory
DESI Press Committee Chair
Email:evlinder@lbl.gov

Josie Fenske
Jr. Public Information Officer
NSF NOIRLab
Email:josie.fenske@noirlab.edu

Lauren Biron
Lawrence Berkeley National Laboratory
Science Communication and Media Relations Specialist
Email:LBiron@lbl.gov

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Sighting forbidden light

MCG-01-24-014

A spiral galaxy. It appears to be almost circular and seen face-on, with two prominent spiral arms winding out from a glowing core. It is centred in the frame as if a portrait. Most of the background is black, with only tiny, distant galaxies, but there are two large bright stars in the foreground, one blue and one red, directly above the galaxy. Credit: ESA/Hubble & NASA, C. Kilpatrick

This whirling image features a bright spiral galaxy known as MCG-01-24-014, which is located about 275 million light-years from Earth. In addition to being a well-defined spiral galaxy, MCG-01-24-014 has an extremely energetic core, known as an active galactic nucleus (AGN), so it is referred to as an active galaxy. Even more specifically, it is categorised as a Type-2 Seyfert galaxy. Seyfert galaxies host one of the most common subclasses of AGN, alongside quasars. Whilst the precise categorisation of AGNs is nuanced, Seyfert galaxies tend to be relatively nearby ones where the host galaxy remains plainly detectable alongside its central AGN, while quasars are invariably very distant AGNs whose incredible luminosities outshine their host galaxies.

There are further subclasses of both Seyfert galaxies and quasars. In the case of Seyfert galaxies, the predominant subcategories are Type-1 and Type-2. These are differentiated from one another by their spectra — the pattern that results when light is split into its constituent wavelengths — where the spectral lines that Type-2 Seyfert galaxies emit are particularly associated with specific so-called ‘forbidden’ emission. To understand why emitted light from a galaxy could be considered forbidden, it helps to understand why spectra exist in the first place. Spectra look the way they do because certain atoms and molecules will absorb and emit light very reliably at very specific wavelengths. The reason for this is quantum physics: electrons (the tiny particles that orbit the nuclei of atoms and molecules) can only exist at very specific energies, and therefore electrons can only lose or gain very specific amounts of energy. These very specific amounts of energy correspond to certain light wavelengths being absorbed or emitted.

Forbidden emission lines, therefore, are spectral emission lines that should not exist according to certain rules of quantum physics. But quantum physics is complex, and some of the rules used to predict it use assumptions that suit laboratory conditions here on Earth. Under those rules, this emission is ‘forbidden’ — so improbable that it’s disregarded. But in space, in the midst of an incredibly energetic galactic core, those assumptions don’t hold anymore, and the ‘forbidden’ light gets a chance to shine out towards us.

Source: ESA/Hubble/potw

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Cosmic Web Lights Up in the Darkness of Space

A mosaic of images captured using W. M. keck Observatory's keck cosmic web imager showing the filaments of gas that make up the cosmic web. the green dots mark known galaxies the filaments connect to. Credit: C. Martin et al./Caltech/W. M. Keck Observatory

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Keck Cosmic Web Imager Offers Best Glimpse Yet of the Filamentous Network That Connects Galaxies

Maunakea, Hawaiʻi Like rivers feeding oceans, streams of gas nourish galaxies throughout the cosmos. But these streams, which make up a part of the so-called cosmic web, are very faint and hard to see. While astronomers have known about the cosmic web for decades, and even glimpsed the glow of its filaments around bright cosmic objects called quasars, they have not directly imaged the extended structure in the darkest portions of space—until now.

New results from the Keck Cosmic Web Imager, or KCWI, which was designed by Caltech’s Edward C. Stone Professor of Physics Christopher Martin and his team, are the first to show direct light emitted by the largest and most hidden portion of the cosmic web: the crisscrossing wispy filaments that stretch across the darkest corners of space between galaxies. The KCWI instrument is based at the W. M. Keck Observatory atop Maunakea in Hawaiʻi.

“We chose the name Keck Cosmic Web Imager for our instrument because we were hoping it would directly detect the cosmic web,” says Martin, who is also the director of the Caltech Optical Observatories, which includes Caltech’s portion of Keck Observatory; other Keck Observatory partners are the University of California and NASA. “I’m very happy it worked out.”

Galaxies in our universe condense out of swirling clouds of gas. That gas then further condenses into stars that light up the galaxies, making them visible to telescopes in a range of wavelengths of light. Astronomers think that cold, dark filaments in deep space snake their way to the galaxies, supplying them with gas, which is fuel for making more stars. In 2015, Martin and his colleagues found “smoking-gun evidence,” as Martin describes it, for this so-called cold-flow model of galaxy formation: a long filament funneling gas into a large galaxy. For this work, they used a prototype instrument to KCWI, the Cosmic Web Imager, which was based at Caltech’s Palomar Observatory.

In that case, the filament was being lit up by a nearby quasar, the bright nucleus of a young galaxy. But most of the cosmic web lies in the desolate territory between galaxies and is hard to image.

“Before this latest finding, we saw the filamentary structures under the equivalent of a lamppost,” says Martin. “Now we can see them without a lamp.”

The new findings appear in a paper published in Nature Astronomy on September 28.

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Detecting the Cosmic Web

This animation reveals a 3-D slice through a network of hydrogen gas filaments that crisscross the spaces between galaxies. The data were collected by the Keck Cosmic Web Imager, or KCWI, which was designed to reveal the structure of this previously hidden component of the universe. The region covered in this observation is about 10.5 billion light-years away. The volume depicted here spans an area of 2.3 by 3.2 million light-years and extends across a depth of 600 million light-years (50 million per segment). Credit: Caltech/R. Hurt (IPAC)

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Martin has been driven to reveal the cosmic web in its full glory ever since he was a graduate student. This detailed imaging of the web, he says, will provide astronomers with missing information they need to understand the details of how galaxies form and evolve. It can also help astronomers map the distribution of dark matter in our universe (dark matter makes up about 85 percent of all matter in the universe, but scientists still don’t know what it is made of).

“The cosmic web delineates the architecture of our universe,” he says. “It’s where most of the normal, or baryonic, matter in our galaxy resides and directly traces the location of dark matter.”

The Feeble Glow of Filaments

The best way to see the cosmic web directly is to pick up signatures of its main component, hydrogen gas, using instruments called spectrometers, which spread light out into a multitude of wavelengths, also known as a spectrum. Hydrogen gas can be identified within these spectra via its strongest emission line, called the Lyman alpha line. Martin and his colleagues designed KCWI to find these faint Lyman alpha signatures across a two-dimensional (2D) image of the cosmos (hence KCWI is known as an imaging spectrometer). The instrument’s first installment covers the “blue” portion of the visible-light spectrum, spanning wavelength ranges from 350 to 560 nanometers. (The second part of the instrument, called the Keck Cosmic Reionization Mapper, or KCRM, which sees the red, or longer-wavelength portion, of the visible spectrum, was recently installed at Keck Observatory).

KCWI’s precise spectrometers can look for the Lyman alpha signatures of the cosmic web across a range of wavelengths. Because of the expansion of the universe, which stretches light to longer wavelengths, gas that is located farther away from Earth has a redder Lyman alpha signature. The 2D images captured by KCWI at each wavelength of light can be stacked together to make a three-dimensional (3D) map of the emission from the cosmic web. For this observation, KCWI observed a region of space between 10 and 12 billion light-years away.

“We are basically creating a 3D map of the cosmic web,” Martin explains. “We take spectra for every point in an image at range of wavelengths, and the wavelengths translate to distance.”

Confusion with the Diffuse Light of Space

One challenge in detecting the cosmic web is that its dim light can be confused with nearby background light that suffuses the skies above Maunakea, including the glow from the atmosphere, zodiacal light from the solar system (generated when sunlight scatters off interplanetary dust), and even our own galaxy’s light.

To solve this problem, Martin came up with a new strategy to subtract this background light from the images of interest.

“We look at two different patches of sky, A and B. The filament structures will be at distinct distances in the two directions in the patches, so you can take the background light from image B and subtract it from A, and vice versa, leaving just the structures. I ran detailed simulations of this in 2019 to convince myself that this method would work,” he says.

The result is that astronomers now have “a whole new way to study the universe,” as Martin says.

“With KCRM, the newly deployed red channel of KCWI, we can see even farther into the past,” says senior instrument scientist Mateusz Matuszewski. “We are very excited about what this new tool will help us learn about the more distant filaments and the era when the first stars and black holes formed.”

Speaking of new ways to view the universe, Martin teamed up with artist Matt Schumaker to translate data from the cosmic web into music for a project called “Spiral, supercluster, filament, wall (after Michael Anderson).” The project celebrates the life of Anderson, who perished along with his fellow astronauts in the Space Shuttle Columbia accident in 2003. Martin, who “pretended the filaments were giant violin strings,” translated the filaments’ masses to frequencies based around the note middle C. The piece can be heard here.

The Nature Astronomy study, titled “Extensive diffuse Lyman alpha emission correlated with cosmic structure,” was funded by the National Science Foundation and Caltech.

Source: W.M.Keck Observatory

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About KCWI

The Keck Cosmic Web Imager (KCWI) is designed to provide visible band, integral field spectroscopy with moderate to high spectral resolution formats and excellent sky-subtraction. The astronomical seeing and large aperture of the telescope enables studies of the connection between galaxies and the gas in their dark matter halos, stellar relics, star clusters, and lensed galaxies. KCWI covers the blue side of the visible spectrum; the instrument also features the Keck Cosmic Reionization Mapper (KCRM), extending KCWI’s coverage to the red side of the visible spectrum. The combination of KCWI-blue and KCRM provides simultaneous high-efficiency spectral coverage across the entire visible spectrum. Support for KCWI was provided by the National Science Foundation, Heising-Simons Foundation, and Mt. Cuba Astronomical Foundation. Support for KCRM was provided by the National Science Foundation and Mt. Cuba Astronomical Foundation.

About W. M. Keck Observatory

The W. M. Keck Observatory telescopes are among the most scientifically productive on Earth. The two 10-meter optical/infrared telescopes atop Maunakea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectrometers, and world-leading laser guide star adaptive optics systems. Some of the data presented herein were obtained at Keck Observatory, which is a private 501(c) 3 non-profit organization operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the Native Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain..

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Rewriting the Past and Future of the Universe

A conceptual diagram of this research. Signals from supernovae (bottom right inset), quasars (middle left inset), and gamma-ray bursts (top center inset) reach Earth in the Milky Way Galaxy (background), where we can use them to measure cosmological parameters. Credit: NAOJ). Download image (2.7MB)

New research has improved the accuracy of the parameters governing the expansion of the Universe. More accurate parameters will help astronomers determine how the Universe grew to its current state, and how it will evolve in the future.

It is well established that the Universe is expanding. But with no landmarks in space, it is difficult to accurately measure how fast it is expanding. So, astronomers search for reliable landmarks. The same way a candle looks fainter as it gets farther away, even though the candle itself hasn’t changed, distant objects in the Universe look fainter. If we know the intrinsic (initial) brightness of an object, we can calculate its distance based on its observed brightness. Objects of known brightness in the Universe that allow us to calculate the distance are called “standard candles.”

An international team led by Maria Giovanna Dainotti, Assistant Professor at the National Astronomical Observatory of Japan (NAOJ), and Giada Bargiacchi, PhD student at the Scuola Superiore Meridionale in Naples, with the aid of the supercomputing facilities at NAOJ run by Kazunari Iwasaki, Assistant Professor at NAOJ and member of the Center for Computational Astrophysics, ushered in a new research field by leveraging the use of a variety of new statistical methods to analyze data for various standard candles such as Supernovae, Quasars (powerful black holes consuming matter in the distant Universe), and Gamma Ray Bursts (sudden flashes of powerful radiation). Different standard candles are useful in different distant ranges, so combining multiple standard candles allowed the team to map larger areas of the Universe.

The new results reduce the uncertainty of key parameters by up to 35 percent. More accurate parameters will help determine whether the Universe will continue expanding forever, or eventually fall back in on itself.

Source: National Astronomical Observatory of Japan (NAOJ)/News

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Release Information:

Researcher(s) Involved in this Release

Maria Giovanna Dainotti (Assistant Professor @ National Astronomical Observatory of Japan, NINS)
Kazunari Iwasaki (Assistant Professor @ National Astronomical Observatory of Japan, NINS)

Coordinated Release Organization(s)

National Astronomical Observatory of Japan, NINS
Space Science Institute
Lund University
National Autonomous University of Mexico (UNAM)

Paper(s)

M. G. Dainotti et al “Reducing the uncertainty on the Hubble constant up to 35% with an improved statistical analysis: different best-fit likelihoods for Supernovae Ia, Baryon Acoustic Oscillations, Quasars, and Gamma-Ray Bursts” in the Astrophysical Journal, DOI:

10.3847/1538-4357/acd63f
M.G. Dainotti et al “Quasars: Standard Candles up to z = 7.5 with the Precision of Supernovae Ia” in the Astrophysical Journal, DOI: 10.3847/1538-4357/accea0

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