Session 5: Focused Discussions—Missions in Definition Mars Science Laboratory (MSL)

1. Session 5: Focused Discussions—Missions in DefinitionMars Science Laboratory (MSL) Michael Meyer, MSL Program Scientist Peter Theisinger, MSL Project Manager

2. Agenda • Science Objectives and Payload • Lander Architecture Issues • Landing approach • Solar vs. RTG power • Mobility Trades - Long range rover vs. Base station/fetch rover • Current Baseline Mission

3. Science Objectives and Payload

4. MSL Science Definition Chronology • Science Definition Team (SDT) • Initiated July 2001 • Final Report October 2001 • NRC New Frontiers in the Solar System—An Integrated Exploration Strategy • Final Report July 2002 • Project Science Integration Group (PSIG) • Initiated October 2002 • PSIG Final Report May 2003 • MSL Announcement of Opportunity • Released April 2004

5. SDT Charter & Results • The SDT was to define and prioritize the science objectives, investigations and measurements of the “2007 Mars Smart Lander Mission”. • SDT evaluated in detail two mission alternatives: • Mobile Geobiology Explorer: A rover capable of traversing beyond the landing error ellipse and making measurements related to the sedimentary geology of the site, focused on paleoclimate and biosignatures. • Multidisciplinary Platform which includes: • a live lander with a drill and associated in-situ instrumentation, meteorology, and geophysics packages, and • a rover capable of traversing in the vicinity of the lander, acquiring samples, and delivering the material to the lander-based instruments, followed by longer traverses to explore surrounding terrains.

6. NASA Re-evaluated MSL Based on SDT Results • Subsequent studies demonstrated that the NASA-allocated budget for MSL would be insufficient to accomplish SDT’s and Project’s initial vision. • Adopting SDT report as baseline, NASA requested a study of whether a descoped MSL mission could accomplish the next logical step in decade-long Mars exploration. • NASA chartered the MSL Project Science Integration Group (PSIG) to accomplish this study.

7. PSIG -- Charter • Work with the MSL Project to define and prioritize options for a scientifically exciting mission that are consistent with the Program directives and budget. • The proposed mission concepts must be consistent with • The mission objectives outlined in the NRC New Frontiers in the Solar System - An Integrated Exploration Strategy (July 2002). • The prioritized objectives, investigations, and measurements outlined by MEPAG (July 2001) • Guidance for this effort includes • the 2001 SDT report; • Program’s long-range planning and the linkage between MSL and MSR.

8. MSL PSIG Results and Findings PSIG identified scientifically exciting (breakthrough) options for the 2009 MSL Mission. • MSL ‘09 can be implemented with substantially reduced complexity and cost compared with the mission concept described by the MSL‘07 Project and SDT. • NASA should adopt Mars Habitability as the science goal for MSL. • Two scenarios are suggested for mission • Ancient Habitability: Highest priority mission; Enthusiastic support • Recent Habitability: Significantly lower priority; Supported • Resources allocated to payload were insufficient to meet the science floor • Mission budget increased by Mars Program • Facilitate instrument maturity to meet mission needs • Mars Instrument Development Program (MIDP) initiated

9. MSL PSIG Prioritized Mission Options • Ancient Habitability Mission • Focus on past life and past habitats (Layered sedimentary deposits and Hydrothermal deposits) • Mid-latitude landing site • Rover to reach and explore target terrains • Highest Priority Mission Option (Enthusiastically supported by PSIG) • Recent Habitability Mission • Focus on recent/present life and habitats (Polar Layered Deposits, Polar Cap Edge, Active hydrothermal system, Liquid Water) • Primarily polar landing site (some mid-latitude) • Rover to reach and explore target terrains • Significantly Lower Priority (Supported by PSIG) • Recent Climate Mission • Focus on understanding present climate (High latitude or polar water ice cap) • Polar landing site • Fixed lander with vertical mobility via drill (PSIG considered lowest priority)

10. The Science Objectives for MSL Explore and quantitatively assess a potential habitat on Mars: A. Assess the biological potential of at least one target environment (past or present). i.   Determine the nature and inventory of organic carbon compounds. ii.   Inventory the chemical building blocks of life (C, H, N, O, P, S). iii.   Identify features that may record the actions of biologically-relevant processes.  B. Characterize the geology of the landing region at all appropriate spatial scales. i.   Investigate the chemical, isotopic, and mineralogical composition of martian surface and near-surface geological materials. ii.   Interpret the processes that have formed and modified rocks and regolith. C. Investigate planetary processes that influence habitability. i.   Assess long-timescale (i.e., 4-billion-year) atmospheric evolution processes. ii.   Determine present state, distribution, and cycling of water and CO2. D. Characterize the broad spectrum of surface radiation, including galactic cosmic radiation, solar proton events, and secondary neutrons. Note: This is not a prioritized list. Above is judged to be the science floor for MSL.

11. Selected Investigations Mast Remote SensingMastCam Imaging, Opacity ChemCam Elemental Abundance, Imaging Contact APXS Element Abundance MAHLI Microscopic Imaging Analytic LaboratorySAM Elements, Isotopes, Organics ChemMin Mineralogy, Element Abundance Environment MonitoringDAN Subsurface Hydrogen REMS Meteorology, UV Radiation RAD Surface Radiation MARDI Landing Site Imaging Total 10

12. Summary • The Mars Science Laboratory mission will explore and quantitatively assess a local region on the Mars surface as a potential habitat for life, past or present. The investigations: • Fit within the stated mission constraints • Meet all the PSIG recommendations & AO/PIP science objectives • Are expected to: • Significantly advance our understanding of the potential habitability of Mars, and • Determine the thrust of science investigations for the following decade.

13. MSL Formulation • Two areas of focus in the MSL formulation: • Implement a design which is responsive to the mission science objectives, and • Within that envelope, implement a design which is consistent with the following missions in the Mars program • Discussion of how MSL and MSR can be coupled will be addressed in the next presentation

14. Lander Architecture Issues • Landing approach • Surface Energy — Solar vs. RTG power • Mobility Trades — Long-range rover vs. • Base station/fetch rover

15. Landing Approach

16. Entry Energy Dissipation Via Aerodynamic Drag Velocity Range: start ~ 5.4 km/s end ~ 430 m/s Guided entry for energy dissipation or precision / pinpoint landing Parachute Descent Energy Dissipation via Aerodynamic Drag Velocity Range: start ~ 430 m/s end ~ 85 m/s The Landing ChallengeArriving at the ground with a velocity within the touchdown system capabilities Powered Descent Energy Dissipation Via Rocket Thrust Velocity Range: start ~ 85 m/s end ~ 2-20 m/s Landing Energy Dissipation Via Viscous Damping or Plastically Crushed Material Velocity Range: start ~ 2 – 20 m/s end ~ 0.0 m/s

17. The Landing Challenge (continued) • The key issue with landing on Mars is solving the “last meter” problem. • The objective of entry and descent is to place the land just above the surface with velocity in the correct rang; and • The objective of the landing system is to successfully touchdown.

18. MSL Landing Studies • Several alternate landing architectures have been studied • Airbags & RAD rockets (MPF, MER) • Advantages include heritage, tolerance to surface conditions, minimal sensor requirements • Disadvantages are mass inefficiency, sensitivity to wind conditions, packaging inefficiency, need for self righting, egress assistance for mobility, altitude capability • Legged landers (Viking, MPL, Phoenix) • Advantages include heritage, mass & packaging efficiency, wind tolerance • Disadvantages include sensitivity to surface conditions, lateral stability concerns, need for egress assistance for mobility

19. MSL Landing Studies • Pallets • Advantages include mass & packaging efficiency, wind & surface tolerance, no self righting, minimal egress assistance for mobility, good lateral stability • Disadvantages include complex/difficult to model ground interactions, close proximity of propulsion system to ground • Skycrane • Advantages are same as pallet, but propulsion system “on top” • Primary disadvantage is need for highly capable touchdown velocity sensor

20. Surface Energy

21. Surface Energy Daily management of energy on MER wasa major factor in what could or could not be accomplished on a given day

22. Surface Energy Sources: • Solar highly variable over the planet because of seasons, orbit eccentricity, orientation and dust • Nuclear sources invariant, but come in quanta (~ 110 We per Multi-mission RTG)

23. Solar Power Availability(Function of Latitude and Martian Season – Ls) Phoenix MSL MPF Opportunity Oppt. Spirit Spirit MPL ’22-II ’22-I ’11-I ’11-II ’13-I ’13-II ’20-II ’16-I ’20-I ’16-II ’18-I ’18-II Spring Summer Fall Winter

24. Hours of Cold Temperature (<40º C)(Function of Latitude and Martian Season – Ls) Phoenix MSL MPF Opportunity Oppt. Spirit Spirit MPL ’20-I ’22-II ’22-I ’11-I ’11-II ’13-I ’13-II ’20-II ’16-I ’16-II ’18-I ’18-II Spring Summer Fall Winter

25. RTG vs. Solar Trade • RTG development is programmatically important to NASA • Multi-mission RTG program restarted to support MSL and other future missions • Solar powered missions have restricted planetary access • Short duration at high latitudes (Phoenix) • Long duration near the equator (MER) • RTG power source allows all season, all planet access • Enables long duration missions • Provides access to scientifically interesting high latitude sites

26. Mobility Trades

27. Range of Architectural Alternatives Stationary Platform+ a Fetch Rover Only a Stationary Platform Take-it-all-with-you Rover Sojourner (11 kg) MER (180 kg) Multiple MER MER+ Sojourner +

28. Rating the Architectural Alternatives • To differentiate among the various architectural alternatives the following set of metrics is considered (not in priority order) • Inherent science merit • Resiliency to discoveries yet to be made before launch by MRO and other assets • Resiliency to landing site surprises after landing • Development risk • Operational complexity • Cost • Scientific feed forward to missions next decade

29. Current Baseline Mission

30. Rover Comparison MSL Baseline MER Sojourner

31. MSL Rover Baseline Design DRL Exit Guide Deployed RSM LGA RTG Heat Exchanger RTG UHF Quad Helix Front Wheel Mobility Restraint Rear Wheel Mobility Restraint Robotic Arm (Stowed) External Differential Rock Crusher Payload Module Fluid Loop Surface Radiators Mobility System

32. Mars Topography 60˚ VL2 30˚ VL1 MPF Beagle 2 Opportunity Isidis Latitude 0˚ Spirit Meridiani Planum Gusev Crater -30˚ -60˚ 180˚ 210˚ 240˚ 270˚ 300˚ 330˚ 0˚ 30˚ 60˚ 90˚ 120˚ 150˚ 180˚ East Longitude

33. MSL Landing Altitude < 2.0 km • Black area is topography > 2.0 km • Lines at ±50º, ±60º latitude

34. Back-up Slides • Traceability – science objectives and MSL investigations • Membership of : • SDT • PSIG

35. MSL Science Traceability to AO/PIP Assess the biological potential of at least one target environment identified prior to MSL, or discovered by MSL.

36. MSL Science Traceability to AO/PIP Characterize the geology and geochemistry of the landing region at all appropriate spatial scales (i.e., ranging from micrometers to meters).

37. MSL Science Traceability to AO/PIP Investigate planetary processes of relevance to past habitability including the role of water.

38. MSL Science Traceability to AO/PIP Characterize the broad spectrum of surface radiation, including galactic cosmic radiation, solar proton events, and secondary neutrons.

39. Raymond Arvidson, Chair Suzanne Smrekar Jeffery Bada David Beaty Alain Berinstain Jean-Pierre Bibring Michael Carr Luigi Colangeli Douglas Cooke Angioletta Coradini Michael Duke Erick Dupuis William Farrell Matthew Golombek John Grant Robert Grimm Robert Haberle Gentry Lee Laurie Leshin Duncan MacPherson Paul Mahaffey Tim McCoy Douglas Ming Kenneth Nealson David Paige Ted Roush Everett Shock Peter Smith Claude d’Uston Michelle Viotti Aaron Zent NASA Hq. Chartered MSL Science Definition Team (SDT) -- (2001)

40. MSL Project Science Integration Group—2003 A multi-disciplined team (science, system engineering) set of skilled individuals selected to formulate MSL Project, Program, Ex-officio Frank Palluconi (MSL Proj. Sci.) Leslie Tamppari (MSL Dep. Proj. Sci.) Matt Golombek (ex-MSL Proj. Sci.) Mike Sander (MSL Proj. Mgr.) Jeff Simmonds (MSL Payload Mgr.) Charles Whetsel (Chief Eng.) Gentry Lee (Chief Eng.) Frank Jordan (Mgr. Adv. Plan.) David Beaty (Mars Sci. Office) Jim Garvin (NASA, Mars Lead Sci.) Bruce Banerdt (NetLander Co-I) Rich Zurek (PS, MRO) Support Marguerite Syvertson Dan McCleese, JPL Jack Farmer, ASU Science Team David DesMarais, ARC Bruce Jakosky, U Colo. Gary Kocurek, U Texas Doug Ming, JSC Paul Mahaffy, GSFC Scott McLennan, SUNY David Paige, UCLA Jeff Taylor, U Hawaii Hunter Waite, U Mich. PSIG Co-Chairs