Piping Up at the Gates of Dawn
By Dennis Overbye, The New York Times.
Excerpt: Since the James Webb Space Telescope began operating two years ago, astronomers have been using it to leapfrog one another millions of years into the past, back toward the moment they call cosmic dawn, when the first stars and galaxies were formed. Last month, an international team doing research as the JWST Advanced Deep Extragalactic Survey, or JADES, said it had identified the earliest, most distant galaxy yet found — [JADES-GS-z14-0] a banana-shaped blob of color measuring 1,600 light-years across. It was already shining with intense starlight when the universe was in its relative infancy, at only 290 million years old, the astronomers said. ...the wavelength of light from JADES-GS-z14-0 had been stretched more than 15-fold by the expansion of the universe (a redshift of 14 to use astronomical jargon), similar to the way a siren’s pitch becomes lower as it speeds away. That means light has been coming toward us for 13.5 billion years, since shortly after the universe began. (The universe is about 13.8 billion years old, according to cosmological calculations.) ...In a blog post, Dr. Carniani and Kevin Hainline of the University of Arizona, another member of the JADES team, wrote: “It is likely that astronomers will find many such luminous galaxies, possibly at even earlier times, over the next decade with Webb. We’re thrilled to see the extraordinary diversity of galaxies that existed at Cosmic Dawn!”