Overview
- The newly released composite combines Chandra X-ray data with Legacy Surveys optical imagery to map superheated gas and the locations of galaxies.
- Observations show over a hundred galaxies embedded in multimillion-degree gas whose mass exceeds that of the galaxies, with dark matter dominating the total mass.
- Comparisons with simulations support two timelines: a first impact more than two billion years ago with a return collision now, or a single collision about 400 million years ago with the clusters moving apart.
- The elongated hot-gas morphology and twin concentrations of galaxies place the system in a rare class of mergers exemplified by the Bullet Cluster.
- Findings reported in The Astrophysical Journal by UC Davis researchers underscore the need for further observations to pinpoint the collision history and probe dark-matter behavior.