Overview
- NASA and the Perseverance science team published their interpretation in the Journal of Geophysical Research: Planets on Wednesday, July 15, 2026, describing the 245‑foot‑thick “Broom Point” member as impact‑derived.
- The team interprets the sequence as older than 3.9 billion years, which would make it among the oldest terrain examined by a Mars rover.
- Layer composition—alternating breccias, fine dust and abundant dark, glassy beads with gas‑bubble cavities—matches material expected from impact melt and ejecta rather than typical volcanic deposits.
- Very steep tilts in some layers led scientists to propose a two‑stage deformation history in which the earlier Isidis Basin impact tilted the rocks and a later Jezero‑forming impact fractured and uplifted them.
- Perseverance collected two cored samples, named “Main River” (March 10, 2025) and “Bell Island” (April 22, 2025), that could yield exact ages and environmental details if a future sample‑return mission brings them to Earth.