Abstract EANA2026-54

Since landing in February 2021, the NASA Mars 2020 Perseverance rover has explored the geology of Jezero Crater, an ancient impact basin that once contained a lake and delta system more than 3.7 billion years ago [1]. The mission aims to collect and preserve Martian rock, regolith, and atmospheric samples for future return to Earth through the NASA–ESA Mars Sample Return program. These samples are expected to provide insights into the geological and climatic evolution of Mars, the history of water on the planet, the nature of ancient habitable environments, and potential traces of an ancient biosphere.

The mission has been divided into several campaigns targeting distinct geological settings. During the Crater Floor campaign, Perseverance collected igneous rocks from the Maaz and Seitah formations. These ultramafic to mafic rocks contain alteration minerals such as carbonates and sulfates produced by water-rock interactions [2]. Dating these samples could constrain the timing of volcanic activity and lake formation within Jezero Crater. The Fan Front campaign focused on sedimentary rocks deposited by ancient fluvial processes at the base of the delta. Although no direct evidence of past life has yet been identified, the samples indicate long-lasting aqueous activity and potentially habitable conditions. Regolith samples were also collected to support studies of Martian dust transport and future human exploration. During the Upper Fan campaign, Perseverance investigated younger sedimentary deposits transported into the crater from nearby terrains, that may preserve information about the ancient crust of the surrounding Nili Planum region and the late stages of delta formation. The Margin Unit campaign revealed rocks rich in olivine, pyroxene, serpentine, and magnesium-iron carbonates, all indicative of extensive water-rock interaction. During the Neretva Vallis campaign, one mudstone sample was found to contain clay minerals, reduced iron phosphates and sulfides, iron oxides, and detectable organic carbon; this redox-complex sample is one of the mission’s most promising astrobiological targets [3]. The ongoing Crater Rim campaign investigates some of the oldest accessible terrains on Mars, possibly older than 4 billion years. These rocks, preserved within megabreccia blocks linked to the Isidis impact basin, record volcanism, impact processes, and hydrothermal alteration.

At present, Perseverance stores 21 sample tubes (two left unsealed), including rock cores, regolith material, and two witness tubes designed to monitor contamination [4]. These samples constitute a unique and return-worthy scientific archive [5] for understanding the climatic, hydrological, and geological history of Mars and assessing its ancient habitability. After their return to Earth, these samples will enable detailed investigations of Mars’s environmental history, prebiotic processes, and possible signs of past life through high-resolution, high-sensitivity laboratory analyses that cannot be performed by rover instruments on Mars and are not achievable through the study of martian meteorites alone.

[1] Farley et al. (2020) Space Sci. Rev. 216. 

[2] Simon et al. (2023) JGR Planets, 128, e2022JE007474. 

[3] Hurowitz et al. (2025) Nature 645, 332–340.  

[4] Herd et a., (2025) PNAS 122 e2404255121 

[5] Zorzano et aL. (2025) Astrobiology 25