1. Filling Mars Human Exploration Strategic Knowledge Gaps with Next Generation Meteorological Instrumentation. S. Rafkin, Southwest Research Institute (rafkin@boulder.swri.edu) D. Banfield, Cornell University R. Dissly, Ball Aerospace Corporation This work has been supported in part by NASA PIDDP NNX12AK49G-S02

2. PREDECISIONAL FOR PLANNING AND DISCUSSION PURPOSES ONLY 2 Analysis of Strategic Knowledge Gaps Associated with Potential Human Missions to the Martian System Precursor Strategy Analysis Group (P-SAG) (jointly sponsored by MEPAG and SBAG) Review copy released May 31, 2012 Review comments received from MEPAG, CAPTEM, SBAG, from community discussions at the LPI Workshop (June 12-14), and from MPPG (June 21) Final report June 30, 2012 Recommended bibliographic citation: P-SAG (2012) Analysis of Strategic Knowledge Gaps Associated with Potential Human Missions to the Martian System: Final report of the Precursor Strategy Analysis Group (P-SAG), D.W. Beaty and M.H. Carr (co-chairs) + 25 co-authors, sponsored by MEPAG/SBAG, 72 pp., posted July 2012, by the Mars Exploration Program Analysis Group (MEPAG) at http://mepag.jpl.nasa.gov/reports/. MOTIVATION

3. PREDECISIONAL FOR PLANNING AND DISCUSSION PURPOSES ONLY There are other atmospheric GFAs identified in the P-SAG report. Measurement Priorities Examples of Atmospheric Gap-Filling Activities Gap filling activityPriorityLocationMeasurements and demonstrations A1-1. Global temperature field.HighMars OrbitGlobal Temperature Field A1-2. Global aerosol profiles and properties HighMars Orbit Aerosol Profiles and properties, including optical properties, particle sizes, and number densities A1-3. Global winds & wind profiles MediumMars OrbitGlobal coverage of wind velocity and direction A2-1. Atm. Modeling.HighEarthImprove atmospheric models B1-1. Dust ClimatologyHighMars OrbitDust and aerosol activity climatology B1-2. Global surface pressure; local weather High Mars surface Surface Pressure and Surface meteorology B1-3. Surface windsMedium Mars surface Vertical Profiling of surface winds from 0-15 km B1-4. EDL profilesMediumMars EDLHigh Vertical Resolution Temperature Profiles B1-5. Atmospheric Electricity conditions Low Mars surface AC and DC electric fields, Ground and atmospheric electrical conductivity, Dust grain charge 3

4. Intent of Atmospheric SKGs Need to characterize the structure and dynamical behavior of the atmosphere. Need to validate models of the atmosphere. Need to improve models of the atmosphere. Need to extrapolate observations to other locations with models. 18 June 2013Rafkin et al.4

5. Why Investigate? Q: What is the density and wind structure at time of landing? A: I don’t know. Here’s a guess. Q: What are the error bars? A: I don’t know. Here’s a guess. Q: Why don’t you know? A: Because the proper payloads have not been flown. Q: So, we’ll have to keep guessing for this and future missions? A: Yes. 18 June 2013Rafkin et al.5

6. Decision More of the same will do little to make significant progress on the atmospheric SKGs. Atmospheric SKG Goals Knowledge Time / Surface Experiments Viking Pathfinder Phoenix MSL 2020 Present state Incremental? major? or Humans on Mars 18 June 2013Rafkin et al.6

7. An Upward Knowledge Trajectory: Forcing Mechanisms Solar Down Infrared Down Infrared Up Latent Heat Flux Sensible Heat Flux Regolith Heat Flux Energy In (forcing) Energy Out (forcing) Change in Internal Energy = Temperature (response) T-> p -> Winds 18 June 2013Rafkin et al.7

8. An Upward Knowledge Trajectory: Forcing Mechanisms Solar Down Infrared Down Infrared Up Latent Heat Flux Sensible Heat Flux Regolith Heat Flux Energy In (forcing) Energy Out (forcing) Change in Internal Energy = Temperature (response) T-> p -> Winds Measuring only T, p, V response provides ambiguous information for reconciling and improving errors in models. 18 June 2013Rafkin et al.8

9. Density Errors Due to Turbulent Flux Density errors of a few percent are significant for entry, descent and landing. 18 June 2013Rafkin et al.9

10. Density Errors Due to Turbulent Flux Density errors of a few percent are significant for entry, descent and landing. 18 June 2013Rafkin et al.10

11. By Measuring Forcing: Better characterize the structure and dynamical behavior of the atmosphere. Better validate models of the atmosphere. Improve models of the atmosphere. More confidently extrapolate observations to other locations with models. 18 June 2013Rafkin et al.11

12. By Measuring Forcing: Better characterize the structure and dynamical behavior of the atmosphere. Better validate models of the atmosphere. Improve models of the atmosphere. More confidently extrapolate observations to other locations with models. Make significant progress on SKGs! 18 June 2013Rafkin et al.12

13. Necessary Measurements Pressure, temperature, winds (response). Radiative Forcing: solar and infrared . Dust opacity (radiative forcing). Heat and momentum fluxes (turbulent forcing). 18 June 2013Rafkin et al.13

14. Necessary Measurements Pressure, temperature, winds (response). Radiative Forcing: solar and infrared . Dust opacity (radiative forcing). Heat and momentum fluxes (turbulent forcing). Flight Heritage 18 June 2013Rafkin et al.14

15. Measuring Fluxes Sonic Anemometer + Tunable Diode Laser Earth Mars field prototype Mars flight engineering model CBE Resources 0.3 kg sensor 2 kg electronics 4 W Mars environmental testing in early Fall. (TRL-6). 18 June 2013Rafkin et al.15

16. Fluxes 18 June 2013Rafkin et al.16

17. Accommodation A perfect instrument poorly accommodated makes a poor experiment. Must ensure proper accommodation. Must minimize spacecraft contamination: – Mechanical – Thermal Extended booms are the most likely solution. 18 June 2013Rafkin et al.17 Want to measure this, not this.

18. Summary New measurements with proper instrument accommodation are needed to achieve many atmospheric SKGs. Previous instrumentation and methods are insufficient. Cannot be done exclusively from orbit. Quantify forcing and response. Turbulent fluxes are a key forcing mechanism. Simultaneously measuring p, T, V, bulk composition, and solar and IR fluxes provides an energy closure experiment. Atmospheric state must be measured at >10 Hz. Most instrumentation is high heritage and low resource. Combined sonic anemometer and tunable diode laser at TRL-6 this Fall. 18 June 2013Rafkin et al.18