Filling Mars Human Exploration Strategic Knowledge Gaps with Next Generation Meteorological Instrumentation.

Filling Mars Human Exploration Strategic Knowledge Gaps with Next Generation Meteorological Instrumentation.

S. Rafkin, Southwest Research Institute(rafkin@boulder.swri.edu)D. Banfield, Cornell UniversityR. Dissly, Ball Aerospace Corporation

This work has been supported in part by NASA PIDDP NNX12AK49G-S022Analysis 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, 2012Review 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, 2012Recommended 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/.MOTIVATIONPREDECISIONAL FOR PLANNING AND DISCUSSION PURPOSES ONLY2PREDECISIONAL FOR PLANNING AND DISCUSSION PURPOSES ONLYThere are other atmospheric GFAs identified in the P-SAG report.Measurement PrioritiesExamples of Atmospheric Gap-Filling ActivitiesGap filling activityPriorityLocationMeasurements and demonstrationsA1-1. Global temperature field.HighMars OrbitGlobal Temperature FieldA1-2. Global aerosol profiles and propertiesHighMars OrbitAerosol Profiles and properties, including optical properties, particle sizes, and number densitiesA1-3. Global winds & wind profilesMediumMars OrbitGlobal coverage of wind velocity and directionA2-1. Atm. Modeling.HighEarthImprove atmospheric modelsB1-1. Dust ClimatologyHighMars OrbitDust and aerosol activity climatologyB1-2. Global surface pressure; local weatherHighMars surfaceSurface Pressure and Surface meteorologyB1-3. Surface windsMediumMars surfaceVertical Profiling of surface winds from 0-15 kmB1-4. EDL profilesMediumMars EDLHigh Vertical Resolution Temperature ProfilesB1-5. Atmospheric Electricity conditionsLowMars surfaceAC and DC electric fields, Ground and atmospheric electrical conductivity, Dust grain charge3PREDECISIONAL FOR PLANNING AND DISCUSSION PURPOSES ONLYIntent of Atmospheric SKGsNeed 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.4Why Investigate?Q: What is the density and wind structure at time of landing?A: I dont know. Heres a guess.Q: What are the error bars?A: I dont know. Heres a guess.Q: Why dont you know?A: Because the proper payloads have not been flown.Q: So, well have to keep guessing for this and future missions?A: Yes. 18 June 2013Rafkin et al.5DecisionMore of the same will do little to make significant progress on the atmospheric SKGs.Atmospheric SKG GoalsKnowledgeTime / Surface ExperimentsVikingPathfinderPhoenixMSL2020Present stateIncremental?major?orHumanson Mars18 June 2013Rafkin et al.6While additional data similar to Viking/MSL would be incrementally useful, such data does little to identify why models are in error, nor does such data provide the confidence to extrapolate model results from one site to other locations; more of the same will do little to make significant progress on the atmospheric SKGs. 6An Upward Knowledge Trajectory: Forcing MechanismsSolar DownInfraredDownInfrared UpLatent Heat FluxSensible Heat FluxRegolith Heat FluxEnergy In(forcing)Energy Out(forcing)Change in Internal Energy=Temperature(response)T-> p -> Winds18 June 2013Rafkin et al.7To make meaningful progress on the relevant SKGs, a new class of meteorological measurements are needed to provide information about atmospheric forcing mechanisms.

7An Upward Knowledge Trajectory: Forcing MechanismsSolar DownInfraredDownInfrared UpLatent Heat FluxSensible Heat FluxRegolith Heat FluxEnergy In(forcing)Energy Out(forcing)Change in Internal Energy=Temperature(response)T-> p -> WindsMeasuring only T, p, V response provides ambiguous information for reconciling and improving errors in models.18 June 2013Rafkin et al.8To make meaningful progress on the relevant SKGs, a new class of meteorological measurements are needed to provide information about atmospheric forcing mechanisms.

8Density Errors Due to Turbulent Flux

Density errors of a few percent are significant for entry, descent and landing.18 June 2013Rafkin et al.920% change in flux represents just a few W/m2 out of hundreds at the surface. 9Density Errors Due to Turbulent Flux

Density errors of a few percent are significant for entry, descent and landing.18 June 2013Rafkin et al.10By 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.11By 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.12Necessary MeasurementsPressure, temperature, winds (response).

Radiative Forcing: solar and infrared .

Dust opacity (radiative forcing).

Heat and momentum fluxes (turbulent forcing).18 June 2013Rafkin et al.13Necessary MeasurementsPressure, 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.14Measuring FluxesSonic Anemometer + Tunable Diode Laser

Earth

Mars fieldprototypeMars flightengineering modelCBE Resources0.3 kg sensor2 kg electronics4 WMars environmental testing in early Fall.(TRL-6).18 June 2013Rafkin et al.15

Fluxes

18 June 2013Rafkin et al.16AccommodationA perfect instrument poorly accommodated makes a poor experiment.Must ensure proper accommodation.Must minimize spacecraft contamination:MechanicalThermalExtended booms are the most likely solution.

18 June 2013Rafkin et al.17Want to measure this,

not this.SummaryNew 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