Harley Katz

Near the galaxy GN-z11, seen just 400 million years after the Big Bang, the James Webb Space Telescope spotted a bright spot. It glows with hot helium — such radiation can only come from very massive stars devoid of heavy elements, that is, the first generation. If confirmed, we are seeing for the f

Analysis of a hundred 'little red dots' (LRDs) with JWST has shown that their ultraviolet light is redder and more compact than that of ordinary galaxies. Spectral lines of carbon, helium, and hydrogen point to extreme conditions around a black hole, whose radiation seeps through a clumpy envelope.

The Webb telescope spotted red dots that look like galactic cores with enormous black holes. But a fresh analysis suggests they might be modest-sized objects wrapped in a dense gas cocoon. Just as fog makes a lantern seem like a huge red ball, the gas distorts our estimates. Inside, there may not be