Summary:
- Astronomers using NASA's Chandra X-ray Observatory and other telescopes have discovered a surprisingly mature galaxy cluster in the early universe, just over 2 billion years after the Big Bang.
- This galaxy cluster, known as CL J1001+0220, contains hundreds of individual galaxies and a large amount of hot gas, indicating it has already gone through a significant amount of evolution.
- The discovery of this mature cluster in the early universe challenges current models of how galaxy clusters form and evolve, and provides new insights into the early stages of the universe's history.