3.3-billion-year-old galaxy may solve Webb’s “little red dots” mystery

Photo credit: NASA, ESA, CSA, STScI, Pierluigi Rinaldi (Steward Observatory); Image Processing: Alyssa Pagan (STScI) Since NASA’s James Webb Space Telescope first revealed mysterious “little red dots” (LRDs) in 2022, astronomers have been racing to understand what these strange objects really are. Compact, extremely distant and glowing red, they appear throughout the early universe, but their true nature has remained elusive. One leading idea is that they are supermassive black holes known as active galactic nuclei. However, they don’t behave quite like the active galactic nuclei astronomers observe in the nearby universe. LRDs are common at high redshift, but their numbers fall sharply at lower redshifts. That difference has raised an important question: What happens to these mysterious objects as the universe grows older? Now, a new study titled 'Beyond the Dot: An LRD-like Nucleus at the Heart of an IR-bright Galaxy and its Implications for High-redshift LRDs' suggests that a spiral galaxy nicknamed the “Saguaro,” seen as it appeared roughly 3.3 billion years after the Big Bang, may finally offer a clue.A possible evolutionary pathA research team led by Pierluigi Rinaldi, now at...