Webb Space Telescope Reveals Breathtaking Cosmic Fireballs – How Universe Became Transparent

Webb SMACS 0723 Crop

Thousands of galaxies flood this near-infrared, high-resolution image of galaxy cluster SMACS 0723 captured by the James Webb Space Telescope. A pair of UCLA-led studies demonstrate some of the scientific advances that the telescope is making possible. Credit: NASA, ESA, CSA, STScI

Astrophysicists shed light on how hydrogen fog burned away after the Big Bang.

  • UCLA astrophysicists are among the first scientists to use the James Webb Space Telescope to get a glimpse of the earliest galaxies in the universe.
  • The studies reveal unprecedented detail about events that took place within the first billion years after the Big Bang.
  • The UCLA projects were among a small number selected by NASA to test the capabilities of the Webb telescope.

The earliest galaxies were cosmic fireballs converting gas into stars at breathtaking speeds across their full extent, reports a study led by the University of California, Los Angeles (UCLA) published in a special issue of the Astrophysical Journal.

The research, based on data from the James Webb Space Telescope, is the first study of the shape and structure of those galaxies. It shows that they were nothing like present-day galaxies in which star formation is confined to small regions, such as the constellation of Orion in our own Milky Way galaxy.

“We’re seeing galaxies form new stars at an electrifying pace,” said Tommaso Treu, the study’s lead author, a UCLA professor of physics and astronomy. “Webb’s incredible resolution allows us to study these galaxies in unprecedented detail, and we see all of this star formation occurring within the regions of these galaxies.”

Treu directs the GLASS–JWST Early Release Science Program, whose first results are the subject of the special journal issue. Another UCLA-led study in the issue found that galaxies that formed soon enough after the Big Bang — within less than a billion years — might have begun burning off leftover photon-absorbing hydrogen, bringing light to a dark universe.

Guido Roberts-Borsani

Guido Roberts-Borsani. Credit: Courtesy of Guido Roberts-Borsani

“Even our very best telescopes really struggled to confirm the distances to such far away galaxies, so we didn’t know whether they rendered the universe transparent or not,” said Guido Roberts-Borsani, a UCLA postdoctoral researcher who led the study. “Webb is showing us that not only can it do the job, but it can do it with astonishing ease. It’s a game changer.”

Those findings are two of many breathtaking discoveries by UCLA astrophysicists who are among the first to peer through a window to the past newly opened by Webb.

Webb is the largest near-infrared telescope in space, and its remarkable resolution offers an unparalleled view of objects so distant that their light takes billions of years to reach Earth. Although those objects have aged by now, light from only their earliest moments has had enough time to travel through the universe to end up on Webb’s detectors. As a result, not only has the Webb functioned as a sort of time machine — taking scientists back to the period shortly after the Big Bang — but the images it’s producing have become a family album, with snapshots of infant galaxies and stars.

Tommaso Treu

Tommaso Treu, Credit: Courtesy of Tommaso Treu

GLASS–JWST was one of 13 Early Release Science projects selected by NASA in 2017 to quickly produce publicly accessible datasets and to demonstrate and test the capabilities of instruments on the Webb.

The project seeks to understand how and when light from the first galaxies burned through the hydrogen fog left over from the Big Bang — a phenomenon and time period called the Epoch of Reionization — and how gas and heavy elements are distributed within and around galaxies over cosmic time. Treu and Roberts-Borsani use three of the Webb’s innovative near-infrared instruments to take detailed measurements of distant galaxies in the early universe.

The Epoch of Reionization is a period that remains poorly understood by scientists. Until now, researchers have not had the extremely sensitive infrared instruments needed to observe galaxies that existed then. Prior to cosmic reionization, the early universe remained devoid of light because ultraviolet photons from early stars were absorbed by the hydrogen atoms that saturated space.

Scientists think that sometime within the universe’s first billion years radiation emitted by the first galaxies and possibly by the first black holes caused the hydrogen atoms to lose electrons, or ionize, preventing photons from “sticking” to them and clearing a pathway for the photons to travel across space. As galaxies began to ionize larger and larger bubbles, the universe became transparent and light traveled freely, as it does today, allowing us to view a brilliant canopy of stars and galaxies each night.

Roberts-Borsani’s finding that galaxies formed faster and earlier than previously thought could confirm that they were the culprits of cosmic reionization. The study also confirms the distances to two of the farthest galaxies known using a new technique that allows astronomers to probe the beginning of cosmic reionization.

For more on this research, see Webb Draws Back the Curtains on an Undiscovered Universe.

References:

“Early Results From GLASS-JWST. XII: The Morphology of Galaxies at the Epoch of Reionization” by T.Treu, A.Calabro, M.Castellano, N.Leethochawalit, E.Merlin, A.Fontana, L.Yang, T.Morishita, M.Trenti, A.Dressler, C.Mason, D.Paris, L.Pentericci, G.Roberts-Borsani, B.Vulcani, K.Boyett, M.Bradac, K.Glazebrook, T.Jones, D.Marchesini, S.Mascia, T.Nanayakkara, P.Santini, V.Strait, E.Vanzella and X.Wang, Astrophysical Journal.
arXiv:2207.13527

“Early Results from GLASS-JWST. I: Confirmation of Lensed z = 7 Lyman-break Galaxies behind the Abell 2744 Cluster with NIRISS” by Guido Roberts-Borsani, Takahiro Morishita, Tommaso Treu, Gabriel Brammer, Victoria Strait, Xin Wang, Marusa Bradac, Ana Acebron, Pietro Bergamini, Kristan Boyett, Antonello Calabró, Marco Castellano, Adriano Fontana, Karl Glazebrook, Claudio Grillo, Alaina Henry, Tucker Jones, Matthew Malkan, Danilo Marchesini, Sara Mascia, Charlotte Mason, Amata Mercurio, Emiliano Merlin, Themiya Nanayakkara, Laura Pentericci, Piero Rosati, Paola Santini, Claudia Scarlata, Michele Trenti, Eros Vanzella, Benedetta Vulcani and Chris Willott, 18 October 2022, Astrophysical Journal Letters.
DOI: 10.3847/2041-8213/ac8e6e

5 Comments on "Webb Space Telescope Reveals Breathtaking Cosmic Fireballs – How Universe Became Transparent"

  1. As spacetime cooled the gaseous dark matter cooled. When it reached the temperature at which dark matter condenses the collapsing dark matter gravitationally pulls the baryonic matter with it into denser clouds forming the cosmic web.

  2. BibhutibhusanPatel | December 26, 2022 at 8:27 pm | Reply

    Satisfactory progress on JWST observations.Each unit in the Octet plays an important role in the formation of supermassive black hole and stars in galaxy.In Octet Rule of evolution of early galaxies first 1 billion years is divided into eight equal unit,thus gives 125 million years to one unit;so,to complete the electronic structure one unit takes further 25 million years thus one unit of octet is 125+25 million years.JWST has cability to observe 125_25 million years after the big bang.Now first two units of the octet are important for evolution of a galaxy,that is,150 million years and 150 million years after the big bang.Dark matter/energy has a value equal to rotation,thus is a part of star dynamics;hence,interpretation must be in the line of star dynamics.

  3. BibhutibhusanPatel | December 26, 2022 at 8:35 pm | Reply

    Satisfactory progress on JWST observations.Each unit in the Octet plays an important role in the formation of supermassive black hole and stars in galaxy.In Octet Rule of evolution of early galaxies first 1 billion years is divided into eight equal unit,thus gives 125 million years to one unit;so,to complete the electronic structure one unit takes further 25 million years thus one unit of octet is 125+25 million years.JWST has cability to observe 125_25 million years after the big bang.Now first two units of the octet are important for evolution of a galaxy,that is,150 million years and 150 million years after the big bang.Dark matter/energy has a value equal to rotation,thus is a part of star dynamics;hence,interpretation must be in the line of star dynamics.

    The facts of observations also has a statistical imprtance for spiral shape galaxies rotating in one direction.

  4. BibhutibhusanPatel | December 27, 2022 at 12:33 am | Reply

    The first unit of octet building 1 billion years after the big bang,that is 125+ or _ 25 million years galaxies are dark.In the second unit of the octet,that is 125 to 250 + 25×(1 or 2) million years after the big bang the galaxies became continuously more and more transparent.But,transparency increases till third unit of the octet according to the theory of coevolution of supermassive black hole and stars in the galaxy.However,this process of transparency is completed before the saturation or maturity of galaxy,that is,half of the octet or .5 billion years after the big bang;where actual time of maturity or saturation of AGN with stars formation is nearly .5 + .05 billion years after the big bang, when both have growth balanced with hydrogen gas cloud mass.

  5. Oddly the fartherst back of the Universe viewabke after the so-called BB has been dragged forward instead of backward after the launch of Webb which is said to be 1B yrs here. Even before the Webb it was 300M yrs after BB. With the Webb launched it was said to push it back by 100M yrs, ie. it can peer back to 200M yrs after BB. What is the chaos all about after Webb launch?

Leave a Reply to BibhutibhusanPatel Cancel reply

Email address is optional. If provided, your email will not be published or shared.