iMars Phase 2 : A Draft Architecture and Science Management Plan ffor the Return of Samples from Mars

The International Mars Exploration Working Group (IMEWG) was formed in 1993 to provide a forum for the international coordination of Mars exploration. In 2007, IMEWG chartered the international Mars Architecture for the Return of Samples Working Group (iMARS WG), which produced a Phase 1 report in 2008 (iMARS, 2008). In 2014, IMEWG chartered an iMARS Phase 2 Working Group, comprising two panels of experts: (i) Engineering and (ii) Science/Earth Operations. The iMARS Phase 2 WG was tasked to provide: • A status report on planning for a Mars Sample Return (MSR) campaign, building on missions and international developments achieved since the iMARS Phase 1 WG issued its report; and • Recommendations for progressing toward campaign implementation, including a proposed sample management plan. This report presents the iMARS Phase 2 WG’s findings. It details top-level campaign requirements that would meet stated science objectives and planetary protection constraints. It presents an updated reference MSR architecture, made of three flight elements and one ground element (termed the 3+1 architecture). It provides technical and programmatic justifications for this architecture and the report also discusses alternatives to the reference architecture. The WG also reports on the status of MSR technology developments conducted by several space agencies around the world, evidence of the willingness of major space stakeholders to invest in MSR implementation. This report elaborates on programmatic considerations relating to MSR, including campaign robustness, international coordination and decision-making, a provisional implementation timeline, and a possible cost-sharing model.