IMPRESS: A Planetary Penetrator Network for Astrobiology, Prospecting, and Exploration of Mars.

The International Mars Prospecting Ride-Share System (IMPRESS) is presented here as a scalable, democratized, and low-cost mission architecture for distributed measurements on the martian surface and in the shallow subsurface. IMPRESS is intended to prospect on Mars in advance of sample return and human exploration. Its primary objective is to survey Mars for extant life, but it also supports geophysical, soil chemistry, resource, and landing-site risk assessments. Instead of relying on soft landers and drilling systems, IMPRESS deploys swarms of planetary penetrators that use descent kinetic energy to emplace instruments 0.2-1 m below the surface. This architecture provides spatial coverage, measurement replication, and mission redundancy. This increases the chance of detecting unevenly distributed biosignatures and gives negative results stronger context. Small penetrator platforms with standardized design, power, and communication interfaces lower the cost per experiment. The probes operate as independent nodes within a network, which enables time-correlated atmospheric, seismic, and environmental measurements that support the broader Mars exploration campaign. Repeatable mission deployments can range from small rideshare implementations with tens of penetrators to larger dedicated campaigns with hundreds or more. We describe the IMPRESS mission architecture, penetrator platforms, compatible payload classes, and how distributed shallow-subsurface surveys reduce scientific and operational uncertainty before future Mars surface activities. Key Words: Planetary penetrators-Mars-Extant life-Planetary protection-Distributed exploration-Rideshare. Astrobiology, 26, 688-699.