Mars sample return requires considerable technical development, and this work cannot be postponed until a few years before launch. NASA is not currently on a path to Mars sample return, because the (admittedly daunting) technology issues have not yet been addressed. A key area that must be addressed concerns the development of the technology for entry, descent, and landing systems, both at Mars and for Earth return. Another important area is so-called go-to mobility—i.e., the ability to identify a rock and have a rover autonomously approach and collect a sample. Such a capability would provide for more efficient sampling. The MSL-designed coring device is a significant advance in sample-acquisition technology, but end-to-end sample acquisition to storage (and possibly packaging) capability must be developed. If samples are cached on the surface, as suggested above, a precision-landing capability will be needed. Retrieving cached samples, perhaps using a short-range rover with no analytical capabilities, could minimize mission complexity and cost. The development of a Mars ascent vehicle and associated mechanisms for spacecraft rendezvous, docking, and sample transfer are required if pre-collected samples are to be lofted into Mars orbit. In either case, a sample-containment mechanism that meets planetary protection requirements must be devised. Finally, Mars sample return will require that a sample-receiving facility on Earth be designed and constructed. Curated returned samples must be isolated from the terrestrial environment, not only for planetary protection, but also to preserve their scientific integrity for future studies.
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14. See, for example, D.S. McKay, E.K. Gibson Jr., K.L. Thomas-Keprt, H. Vali, C.S. Romanek, S.J. Clemett, X.D.F. Chillier, C.R. Maechling, and R.N. Zare, “Search for Past Life on Mars: Possible Relic Biogenic Activity in Martian Meteorite ALH 84001,” Science 273:924-930, 1996.
15. L. Becker, L.B. Popp. T. Rust and J.L. Bada, “The Origin of Organic Matter in the Martian Meteorite ALH 84001,” Earth and Planetary Science Letters 167:71-79, 1999.