1. Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Planetary Probes as Precursors For a Human Mars Mission Rob Grover Jet Propulsion Laboratory California Institute of Technology International Planetary Probe Workshop 10 6/20/2013 Rob Grover Jet Propulsion Laboratory California Institute of Technology International Planetary Probe Workshop 10 6/20/2013 Copyright 2013 California Institute of Technology Government sponsorship acknowledged Copyright 2013 California Institute of Technology Government sponsorship acknowledged

2. Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Probes Becoming Precursors  President of the United States has set a challenge of humans to Mars orbit by 2030s  One possible scenario is humans to Mars orbit by 2033 followed by a landing in 2038  That would leave 25 years from IPPW 10 to a human landing on Mars  Key events on the road to a human landing Identification of a baseline EDL architecture to land humans safely Development of the key EDL technologies to execute the architecture Precursor missions to demonstrate developed EDL technologies  NASA has mandated all robotic Mars missions shall contribute toward a human Mars mission  Arrived at the point where future robotic science mission planning merges with human precursor mission planning 2 Pre-decisional For Planning and Discussion Purposes OnlyInternational Planetary Probe Workshop 10

3. Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration NASA’s Mars Design Reference Architecture 5 3 International Planetary Probe Workshop 10Pre-decisional For Planning and Discussion Purposes Only

4. Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration 4 International Planetary Probe Workshop 10 Current EDL Baseline Architectures  Element Masses 80 to 100 ton entry mass 40 ton landed payload  EDL Sequence of Events Entry from Mars orbit at 4.8 km/s Hypersonic and supersonic flight with aeromaneuvering for precision landing Transition event from supersonic flight to powered descent under rocket power at about Mach 2 to Mach 3 Maneuvering for precision landing followed by soft touchdown Transition Event JPL TeamX HIAD Concept NASA Habitat Lander ConceptNASA Cargo Lander Concept NASA EDL-SA Architectures 23 m Diameter 10 x 30 m Mid L/D Aeroshell Pre-decisional For Planning and Discussion Purposes Only

5. Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration 5 International Planetary Probe Workshop 10 NASA OCT EDL Roadmap  NASA Office of the Chief Technologist Technology Roadmaps EDL Roadmap – Technology Area 9 Charts out path for developing key EDL technology areas Pre-decisional For Planning and Discussion Purposes Only

6. Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Enabling EDL Technologies (1/2) 6  Thermal Protection Systems Dual-pulse capable TPS Flexible TPS for inflatables -Stowable & capable of 20-150 W/cm 2  Inflatable Decelerators HIAD for hypersonic deceleration -Guidance & control method challenges -Flexible structure leading to potential for fluid/structure interaction SIAD to augment supersonic deceleration -Augment separation events International Planetary Probe Workshop 10 HIAD Entry at Mars SIAD Rocket Sled Test Apparatus Pre-decisional For Planning and Discussion Purposes Only

7. Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Enabling EDL Technologies (2/2) 7  Supersonic Retro-Propulsion (SRP) Forces and torques from start up transients are a concern Structural dynamics induced in engine structure also a concern  Deep Throttle Descent Engines Deep throttle engines required to allow both high thrust deceleration and low thrust soft touchdown  Plume-Soil Interaction / Site Alteration Potential of high thrust engines to significantly excavate surface International Planetary Probe Workshop 10 SRP Fluid Structure MSL Plume Site Excavation Pre-decisional For Planning and Discussion Purposes Only

8. Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Precursor Missions 8  Future Mars Sample Return is generally viewed as having the potential to exercise many of the mission elements needed for a human mission Mars EDL Mars Ascent Potentially Mars in-situ resource utilization  Mars Sub-Scale Precursor Mission Concepts NASA HEOMD & SMD study Traded three options -1:10 scaling (Delta-IVH) -1:5 scaling (Falcon H) -1:4 scaling (Dedicated SLS) Larger missions better International Planetary Probe Workshop 10Pre-decisional For Planning and Discussion Purposes Only Mars Sample Return Conceptual Design

9. Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Human Mars Surface Mission Crew to Mars Trans-Earth Injection (option) Ascent Maneuvers EDL/Descent Maneuvers Aerocapture Mars Orbit Low Mars Orbit Insertion (option) High Mars Orbit (250 x 33,813 km) ~500 Days at Mars ~720 Days at Mars Aerocapture Mars Orbit EDL/Descent Maneuvers MSR-EDL Tech Demonstration Ascent Maneuvers Trans-Earth Injection ~500 Days at Mars High Mars Orbit (250 x 33,813 km) Demonstrate Aerocapture Demonstrate Aeroentry Demonstrate Supersonic Retropropulsion Demonstrate ISRU and Surface Power Demonstrate Cryo Propellant Storage Demonstrate full-scale CH4/LOX engine  Key Risk: Aerocapture  Key Risk: Aeroentry of Large Vehicles  Key Risk: CH4/LOX engine  Key Risk: ISRU and Surface Power  Key Risk: Cryo Propellant Storage  Key Risk: CH4/LOX engine Precursor Missions Concepts – EDL Risk Reduction From Charles Whetsel, et al, Collaborative Study Mars Sub-scale Precursor Mission Concepts Pre-decisional For Planning and Discussion Purposes Only

10. Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Landed Mass Capability 10  A significant increase in landed mass capability over the next 25 years is required for NASA’s current human mission architecture Mass (ton) Year Pathfinder MER Phoenix MSL InSight Mars 2020 Human Mission Mars Projection Mars requires about 50x increase in landed mass in 20 years Apollo was about a 24x increase in landed mass Apollo Experience Apollo 11 International Planetary Probe Workshop 10Pre-decisional For Planning and Discussion Purposes Only

11. Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Conclusions (Personal Opinion)  If we are truly planning to land humans on Mars in 25 years, robotic Mars landers must be the precursor missions Current NASA budget profile allows for only one path of technology development Continue the current science driven missions and combine with human mission technology development objectives  If we are to build off our current capability, the first human Mars landers must be reasonable in size There are not enough flight opportunities in the next 25 to robustly develop and demonstrate the massive systems envisioned by the current NASA reference architecture Additionally, human Mars landers must have a clear evolutionary path from today’s EDL systems -Favors blunt body style human mission entry systems 11 International Planetary Probe Workshop 10 Any viable strategy should be developed in the context of the international space community Pre-decisional For Planning and Discussion Purposes Only

12. Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology National Aeronautics and Space Administration 12 Human Spaceflight Architecture Team Discussion