JWST and Chandra spot massive protocluster that defies early-universe timing

Using JWST's infrared data and Chandra's X-ray observations, astronomers report JADES-ID1, a massive protocluster about 12.7 billion light-years away, containing at least 66 galaxies and a surrounding hot gas cloud; its mass is estimated at ~20 trillion suns and it spans ~1.1 million light-years, existing when the universe was ~1 billion years old, challenging models that such large structures should form later by 2–3 billion years after the Big Bang.