Optimization of 2005 sample return for Mars exopaleontology

The strategy for Mars exopaleontology has its basis in principles derived from the Earth's Precambrian fossil record, as well as studies of fossilization processes in modern environments that are plausible analogs for the early Earth and Mars. Attention is here given to such requirements for a 2005 sample return mission as high-resolution orbital imaging in 2001, balloon missions, and precursor landed surface missions in 2001-2003.