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Summary Studies were undertaken to develop genetic principles for the restoration of spinifex grasses (Triodia spp.) at the Argyle Diamond Mines in northern Australia. The study used random amplified polymorphic DNA (RAPD) DNA markers to provide a molecular delineation of provenance boundaries for two species Curly Spinifex (Triodia bitextura) and Triodia bynoei and to provide measures which ensure replacement of local genetic diversity. Within‐population diversity measures (0.44 ± 0.03 T. bitextura and 0.32 ± 0.04 T. bynoei) and the proportion of diversity attributed to between‐population differences (≈ 12%) by analysis of molecular variance (AMOVA) indicate extensive out‐crossing in these seeder species. As such, both species should be restored using seed‐based methods to maintain natural diversity. Significant groups of populations (P < 0.05) identified by AMOVA correspond directly to clustering of populations in a dendogram drawn using UPGMA, indicating significant provenances in both species. For T. bitextura, a significant genotypic variation identified at 60 km from mine populations was not evident at 30 km. Seed for restoration at the mine should, therefore, be harvested from within 30 km of the area to be restored to ensure maintenance of the local provenance. Two T. bynoei populations located 2 km apart were found to represent a single genotype, all other populations were identified as separate genotypes. The majority of the isolated T. bynoei populations, therefore, represent distinct provenances. For both species, in excess of 80% of the measured species diversity occurred in just 20 individuals. As restoration of these grasses will necessitate harvesting seed from thousands of plants the species capacity for evolutionary change should be maintained. With continuing improvements in the effectiveness of molecular genetics technology, the assessment of provenance boundaries through the use of genetic markers is becoming a realistic option for the development of more genetically representative sourcing of genotypes in plant restoration programmes.

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Entry, descent, and landing (EDL) is a multidimensional, complex problem, which is difficult to visualize in simple plots. The purpose of this work is to develop a systematic visualization scheme that could capture Mars EDL trades as a function of a limited number of variables, such that programmatic design decisions could be effectively made with insight of the design space. Using the Mars Science Laboratory (MSL) as a basis, contour plots have been generated for key EDL figures of merit, such as maximum landed elevation and landed mass as a function of four input parameters: entry mass, entry velocity, entry flight path angle, and vehicle L/D. Additionally, sensitivity plots have been generated in an attempt to capture the effects of varying the fixed input parameters. This set of EDL visualization data has been compiled into a Mars EDL handbook to aid in pre-phase A design space exploration and decision making. Nomenclature DSM = Design Structure Matrix EDL = Entry, Descent, and Landing FPA = Flight Path Angle L/D = Lift to Drag Ratio MER = Mars Exploration Rovers MSL = Mars Science Laboratory PESST = Planetary Entry System Synthesis Tool POST = Program to Optimize Simulated Trajectories TPS = Thermal Protection System