However, astronomers have not yet confirmed the redshifts of either HD1 or GLASS-z11. Even more recently, early results from Webb have identified another candidate galaxy at redshift 13, called GLASS-z11. The higher the redshift factor, the more distant the lightsource.)Īn even more distant candidate is HD1, discovered at a redshift of 13, appears to us as it did just 300 million years after the Big Bang. ("Redshift" refers to the stretching of the wavelength of light that occurs as the universe expands between a distant object and the viewer. The current most distant confirmed galaxy is a faraway object known as GN-z11, which has a redshift of 11.09, meaning we see it as it existed 13.4 billion years ago, just 400 million years after the Big Bang. "Our models not only describe the mass, but we can also use them to describe the magnification of these lensed images," Pascale told. (Image credit: NASA/ESA/CSA/STScI/Pascale et al.) One of the new papers, from a team led by Guillaume Mahler of Durham University, concluded that most of the mass is centered on the brightest, most massive galaxy in the cluster.Įxamples of some of the lensed background galaxies in Webb's image of SMACS J0723. Whatever the final tally, these lensed images allow scientists to finetune a map of how matter - both visible and dark - is distributed in the SMACS J0723 cluster, and in turn model the shape of the lens. Another team, led by Gabriel Caminha of the Max Planck Institute for Astrophysics in Germany, counted 27 new lensed images. Gravitational lenses can create multiple images of the same galaxy, so these 42 images represent 19 individual galaxies. But Webb takes the hunt to a whole new level.įrye's team, which was led by graduate student Massimo Pascale at the University of California, Berkeley, discovered 42 new lensed images in the background of the new deep-field image. Previous surveys by the Hubble Space Telescope and the retired Herschel Space Observatory had found a handful of lensed images of background galaxies in their SMACS J0723 observations. Galaxy clusters are particularly efficient lenses because they pack a huge amount of mass (in the case of SMACS J0723, about 100 trillion times the mass of the sun) into a relatively compact volume with a diameter of about 3 to 5 million light-years across. Gravitational lensing is a phenomenon in which a very massive object's gravity warps space into a shape analogous to an optical lens, resulting in light from whatever is behind the lens being distorted and magnified in brightness. "It was beautifully chosen because it was a relatively unknown target," she said.
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