![]() The hundreds of galaxies offer a view almost into the very opening scenes of the cosmos, and they show that things were different then.Ībout a sixth of early galaxies in the JADES sample are in the throes of star formation of a kind we don’t see in the nearby universe, Endsley explains, marked by extremely bright emission at certain wavelengths. But the JADES team assuaged that concern: Of 42 galaxies followed up with spectra, from which astronomers can obtain more fool-proof redshift measurements, there were no masqueraders. Using that method, it’s possible for dusty, relatively nearby galaxies to masquerade as more distant sources. Astronomers first gauged their distances by a method that depended on measuring their brightness at each of several color bands. Some in the community had been concerned that not all of these so-called early galaxies were really in the early universe. The sample also provided opportunity for reassurance. “This,” Hainline declares, “is the rest of the iceberg.” ![]() Now, 93% of the galaxies JWST is picking up are new, never identified before. “These are the galaxies that are starting the process of making the elements and the complexity that we see in the world around us today.”īefore JWST, Hubble saw two luminous galaxies at such early times (redshifts greater than 10). “This is important because we live in a universe of complexity, and the early universe was hydrogen, helium and light,” Hainline says. Carniani (Scuola Normale Superiore), and the JADES Collaboration Color composite JWST NIRCam image of the galaxy JADES-GS-z13-0, the most distant, spectroscopically confirmed galaxy known so far. If the entire history of the universe were a two-hour movie, then these galaxies are enabling us to watch, for the first time, scenes from the first two to five minutes. The most distant of these - “the farthest galaxy humans have ever seen,” Hainline says - is spectroscopically confirmed to be at a redshift of 13.2, or just 325 million years after the Big Bang. The JADES team has so far discovered 717 galaxies at redshifts greater than 8, when the universe was just 600 million years old. These galaxies reveal the chaotic state of the universe as it was just hundreds of million years after the Big Bang. But this newest, deep-sky stare is on a whole different level, with 32 days’ worth of telescope time, infrared wavelengths that allow JWST to see more distant galaxies than any telescope before it, and a much bigger viewing area than Hubble was capable of.Įven as the JADES program continues to collect data, team members Kevin Hainline (Steward Observatory) and Ryan Endsley (The University of Texas at Austin) announced at a press conference of the 242nd meeting of the American Astronomical Society the discovery of hundreds of early galaxies. The James Webb Space Telescope (JWST) Advanced Deep Extragalactic Survey (JADES) is basically the next-gen version of the Hubble Deep Field. ![]() ![]() NASA / ESA / CSA / Brant Robertson (UC Santa Cruz) / Ben Johnson (CfA) / Sandro Tacchella (Cambridge) / Marcia Rieke (University of Arizona) / Daniel Eisenstein (CfA) Image processing ![]()
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