Astronomers have revealed the latest deep-field image from NASA’s James Webb Space Telescope, featuring never-before-seen detail of a region of space known as the Pandora Cluster (Abell 2744). Webb’s view shows three already massive galaxy clusters joining together to form a megacluster. The combined mass of galaxy clusters creates powerful gravitational lensing, which is a natural enlarging effect of gravity, allowing much more distant galaxies in the early universe to be observed using the cluster as a magnifying glass.
Only the central core of Pandora has previously been studied in detail by NASA’s Hubble Space Telescope. By combining Webb’s powerful infrared instruments with a wide mosaic view of the different gravitationally lensed areas of the region, the astronomers were trying to achieve a balance of breadth and depth that will open a new frontier in the study of cosmology and the evolution of galaxies.
“The ancient myth of Pandora is about human curiosity and discoveries that delineate the past from the future, which I think is an apt connection to the new realms of the universe that Webb is discovering, including this deep-field image of the Pandora cluster. said astronomer Rachel Bezanson of the University of Pittsburgh in Pennsylvania, co-principal investigator for the NIRSpec and NIRCam Ultra-Deep Observations Before the Reionization Era (UNCOVER) program to study this region.
“When Webb’s images of the Pandora cluster first came in, honestly, we were a bit dazzled,” Bezanson said. “There was so much detail in the foreground cluster, and so many distant galaxies with gravitational lensing, that I got lost diving into the image. Webb exceeded our expectations.” The new view of the Pandora Cluster stitches together four Webb images into a single panorama, showing around 50,000 near-infrared light sources.
In addition to increasing their size, gravitational lensing distorts the appearance of distant galaxies, making them look very different from those in the foreground. The “lensing” of the galaxy cluster is so massive that it warps the fabric of space itself, enough so that light from distant galaxies passing through that warped space also takes on a lopsided appearance.
Astronomer Ivo Labbe, of Swinburne University of Technology in Melbourne, Australia, who is co-principal investigator for the UNCOVER program, said that in the core of the gravitational lens at the bottom right of Webb’s image — which has never been photographed by the Hubble telescope—Webb revealed hundreds of distant gravitationally lensed galaxies that appear as faint arcing lines in the image. Zooming in on this region reveals more and more of these galaxies.
“The Pandora cluster, as imaged by Webb, shows us stronger, wider, deeper and better gravitational lensing than we’ve seen before,” Labbe said. “My first reaction to this image was that it was so beautiful it looked like a simulation of galaxy formation. We had to remind ourselves that this was real data and that we are now working in a new era of astronomy.”
The UNCOVER team of researchers used Webb’s Near Infrared Camera (NIRCam) to capture the cluster, with exposures lasting four to six hours, for a total of about 30 hours of observing time. . The next step is to meticulously review the image data and select the galaxies for follow-up observations with the Near Infrared Spectrograph (NIRSpec), which will provide precise distance measurements, along with other detailed information. on the composition of gravitational lensing galaxies, offering new insights into the early era of galaxy formation and evolution. The UNCOVER team hopes to make these NIRSpec observations in the summer of 2023.
In the meantime, all NIRCam photometric data has been made public so that other astronomers can become familiar with it and plan their own scientific studies with Webb’s rich data sets. “We are committed to helping the astronomical community make the best use of the fantastic resource we have with Webb,” said co-investigator Gabriel Brammer, from the Niels Bohr Institute’s Center for Cosmic Dawn at the University of Copenhagen. “This is just the beginning of all the amazing Webb science to come.”
The image mosaics and the font catalog [de luz] in the Pandora cluster (Abell 2744) provided by the UNCOVER team combine publicly available Hubble data with Webb photometry from three first observing programs: JWST-GO-2561, JWST-DD-ERS-1324 and JWST-DD -2756.
The James Webb Space Telescope is the world’s premier space science observatory. Webb will solve the mysteries of our solar system, see beyond distant worlds around other stars, and explore the mysterious structures and origins of our universe and our place in it. Webb is an international program run by NASA with its partners: the European Space Agency (ESA) and the Canadian Space Agency (CSA).
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