Overview
- A Science paper published Oct. 29, 2026 reports that Teghaza 001, a gabbro recovered from the Sahara in 2022, formed at least 4.1 billion years ago and is among the oldest Martian igneous rocks analyzed on Earth.
- Researchers used multiple, independent dating methods including uranium–lead ages from zircon crystals and rubidium–strontium analyses to reach consistent ages around 4.1 billion years.
- Chemical and mineral signals—heavy oxygen and hydrogen isotope ratios, sodium-rich alteration rims, manganese‑rich domains and altered phosphates—record hot fluids moving through the rock as it cooled in the Martian subsurface.
- Orbital composition comparisons narrow likely origins to the ancient southern highlands, with the team listing about 13 candidate source locations, while noting that loss of in situ context from desert‑trade recovery limits precise provenance.
- Geochemical models indicate a heterogeneous, garnet-bearing mantle source at depth, the finding strengthens arguments for a wetter early Mars but does not prove past life and underscores the need for targeted, contextual sample‑return missions.