Exploration Strategies at the Arkaroola Mars-Oz Site: Implications for Mars

1. Exploration Strategies at the Arkaroola Mars-Oz Site: Implications for Mars This paper examines the methods and risks when exploring ‘Mars like’ sites of scientific interest at Arkaroola in South Australia. The sites are compared to Gusev Crater and Meridiani Planum. Jon Clarke, Australian Centre for Astrobiology Macquarie University NSW 2109 Australia David Willson, SEMF Hobart Australia david.willson@semf.com.au

2. Exploration Assumptions & Scales • Exploration as per the Mars-Oz mission architecture to ‘Mars like’ sites at Arkaroola assumes the following: • 4 astronauts with 2 being away from the base at any time; • A small teleoperated rover; • A single un-pressurized rover; and, • A large pressurized rovers. • We envisage exploration at four scales: • Short range – On foot; • Medium range – By un-pressurized rover; • Long range – By pressurized rover; and • Extended range – By combined pressurized and un-pressurized rovers.

3. Short Range Exploration • Short Range Exploration – By foot: • We assume an 8 hour maximum duration EVA in pairs; • The authors experience on Earth suggests 5 –15 km travel distance is possible; • The longest Apollo EVA (Apollo 14 EVA-2) was a total of 4 km; • We see the risks associated with EVAs will significantly reduce the range of this type of exploration. The main EVA limitations due to risks are; • Returning to the rover or base before nightfall as the explorer could become lost. • A failure of a suit environmental system. In this case the explorer would connect via an umbilical to his EVA partners unit and share the air supply and cooling. • Suit damage or injury. • We note that radiation from solar flares is a hazard. We suggest exploration would be limited or curtailed during high risk periods. • In addition, the space suit design is a factor in EVA planning. The use of a high mobility suit such as the mechanical counter-pressure suit will; • Reduce the energy required to move by the explorers;and, • Reduce the possibility of suit damage and injury through slipping or falling over. • Conclusion: Allow in exploration plans a 2 km radius covering an area of 12 km².

4. Medium and Long Range Exploration • Medium range exploration – By un-pressurized rover: • The Apollo lunar rover had a battery range of 100 km; • The Apollo rover range was limited to 10 km to ensure the astronauts could return to the LM on foot if the rover failed; and, • Likewise, an un-pressurized rover on Mars could also fail or become bogged. • We also note the un-pressurized rover does not have protection against radiation from solar flares. As per ‘exploration on foot’ exploration would be limited or curtailed during high risk periods. • Conclusion: Allow in exploration plans a 10 km radius for the pressurized rover covering an area of 300 km². • Long range exploration – By pressurized rover: • The MSA Starchaser Marsupial Rover is expected to have a range of 500 km with 2 explorers for 4 days with 20% reserve; • The pressurized rover is expected to be equipped with a radiation storm shelter; • The pressurized rover could still fail or become stuck. The un-pressurized rover would be used to rescue the explorers. • Conclusion: Allow in exploration plans a 40 km radius for the pressurized rover covering an area of covering 5000 km².

5. Extended Operations Extended range – By combined pressurized and un-pressurized rover: Extended range operations could be done by carrying the un-pressurized rover on the pressurized rover. If the pressurized rover fails or becomes stuck the explorers can return to the base in the un-pressurized rover. The un-pressurized rover has a range of 100 km. In this way the over all safe exploration can be extended. Conclusion: Allow in extended exploration plans a 100 km radius for the combined pressurized and un-pressurized rovers covering an area of 3000 km². Hills in Gusev crater

6. Features at Arkaroola that compare with Mars Neoproterozoic basalts (Wootlana volcanics) the hills in the distance are Sturtian tillites. Basalts are in abundance at Gusev Crater, Mars The prime Mars-Oz site Short Range Exploration – By foot

7. Features at Arkaroola that compare with Mars Medium Range Exploration– By un-pressurized rover Paralana radioactive hot (80ºC) artesian spring supporting specialised micobiology. These features provide counterparts to possible Martian features that may contain niches for Martian extremophiles. Protozoic rippled sandstone. Evidence of water as per Meridiani Planum

8. Features at Arkaroola that compare with Mars Long and Extended Range Exploration – By un-pressurized rover Sief Dunes as per Gusev Crater • North Flinders Rangers providing: • Early Cambrian fossiliferous carbonates & clastics. • Cretaceous shoreline deposits; • Gibber plains; and • Artesian springs and seeps. • Area is similar to Louros Vallis a tributary to Vallis Marineris on Mars.