Developing Operational Scenarios for Asteroid Exploration Background, Scenarios, Activities,

1. Developing Operational Scenarios for Asteroid Exploration Background, Scenarios, Activities, Based on Report of HEFT NEO User Team 9/27/10 Presented by P.E. Clark (IACS/CUA) Team Members include P.E. Clark, and C. Weisbin (Lead), W. Lincoln, J. Mrozinski, V. Adumitroaie, H. Hua, K. Shelton, J.H. Smith, A. Elfes (NASA/JPL) Clark et al, FESWG, Asteroid Exploration, 4/18/13

2. Study Focus • Explore NOW (NEO Objectives Workshop (August 2010) • Objectives • 1. Demonstrate deep space capabilities: operations, human health, systems • 2. Characterize NEOs – composition, porosity, size, spin rate, binary, etc. • 3. Mitigate the threat of NEOs to planet Earth • Primary activities • 1. Sample Collection, examination handling • 2. Testing hardware and software systems • 3. Deploying scientific instruments • 4. Testing NEO deflection techniques • Top-level phases of a mission to a NEO: • LEO preparation • Outbound transit to a NEO • NEO operations – human spacecraft, • EVA, science and robotics (focus here) • 4. Earth return transit Clark et al, FESWG, Asteroid Exploration, 4/18/13

3. Science Focus Sampling Strategy for Asteroid Study addresses following issues (from NASA requested New Opportunities in Solar System Exploration, 2007): 1. Processes that marked initial stages of planet and satellite formation (bulk composition versus solar distance, interior structure and evolution) 3. How did impactor flux decay during the solar system’s youth and influence the timing of life’s emergence on Earth? (history and role of early impacts, impactor flux  in early solar system and calibraiton of impact record, how impacts alter body's history, evolution, orbital dynamics) 4. What is the history of volatiles, especially water? (distribution, character, origin of volatiles, potential resources) 11. How do the processes that shape the contemporary character of planetary bodies operate and interact? (absolute ages of samples, recent cratering history and current flux, potential resources) Clark et al, FESWG, Asteroid Exploration, 4/18/13

4. Estimation of Number of Sites, Time • Estimated from maps derived either from • 1. Precursor mission • 2. Real time evolution during visit of human mission • Example taken from Itokawa • Path identification • Estimation of number of stops: Very preliminary results • Variables (path length, site diameter, time at each site, human mobility speed) • Constraints (8 hr/day EVA) Clark et al, FESWG, Asteroid Exploration, 4/18/13

5. Path 1 Path 3 Path 2 Potential Rendezvous Site Smoother Deposits (Regolith Pools, Lower Albedo features) Unusual Albedo (bluish) features Bright Albedo Features, Exposed Structures Hayabusa Touchdown Clark and Clark, 2013, Chapter 6 in Constant Scale Natural Boundary Mapping to Reveal Global and Cosmic Scale Processes, Springer Brief. Clark et al, FESWG, Asteroid Exploration, 4/18/13

6. How many sites? • Used Itokawa (535 × 294 × 209 m) as example to bound answer for other NEOs. • Site is ~10m. • 3 illustrative exploration paths indentified: • Path 1: 8 sites, ~350m length one-way. • Path 2: 7 sites, ~300m length one-way. • Path 3: 6 sites, ~400m length one-way. • Total number sites = 21. • Rough estimate of EVA time required: • Assumed 1 hour per site. • Assumed speed of 3m/min hand-over-hand using tethers/jet pack (need to confirm with analog testing and precursor characterization). • 8 hour per day EVA constraint requires paths done over multiple EVAs. Clark et al, FESWG, Asteroid Exploration, 4/18/13

7. Surface coverage analysis results • Inputs: Diameter of NEO, Number of sites, Diameter of site, Time to explore site, Time to move from site to site. • Outputs: Percent coverage of surface, Total time to explore all sites. • Assume sites are distributed uniformly over NEO surface. • Assume sites are located on a loop for an EVA (i.e. start and end are same location). Clark et al, FESWG, Asteroid Exploration, 4/18/13

8. Characterization of Potential Activities • Tasks • Target number of times performed • Estimated time for task • Number of astronauts engaged • *Note that these are initial targets for planning purposes and will change when better data is acquired • *Specific instruments and payloads can be identified once there is concurrence re: target tasks Clark et al, FESWG, Asteroid Exploration, 4/18/13

9. Science, Resource & Planetary DefensePotential Tasks for NEO surface * Continuous Context Survey – forming theory of NEO history, selecting potential samples ** Highly selected rock acquisition –geochem. instrument to validate interest, document, package Times extrapolated from Apollo Lunar Surface Journal Clark et al, FESWG, Asteroid Exploration, 4/18/13

10. Potential IVA tasks • Station keeping and orbiting of NEO • Testing NEO deflection techniques • Test deflection methods (e.g. gravity tractor, kinetic impact, other slow push/pull techniques) • Observe the effects of laser and solar concentrators on surface materials • Human Health and Research • Develop and test regenerative life support for long-duration missions without resupply • Understand human factors on long-duration missions • Assess human capabilities to tolerate radiation exposure, isolation and confinement, and bone and muscle loss Clark et al, FESWG, Asteroid Exploration, 4/18/13

11. Questions? Clark et al, FESWG, Asteroid Exploration, 4/18/13

12. Surface coverage analysis • How can we get an estimate of the number of sites without a map? • Estimate using surface coverage analysis. Site diameter Distance between sites Hexagon area = 6 * 1/2 * base * height = sqrt(3)/2 * distance between sites^2 Number of potential sites = NEO surface area / area of a hexagon = (2/sqrt(3)) * NEO surface area / distance between sites ^2 Clark et al, FESWG, Asteroid Exploration, 4/18/13