Space Radiation Protection, Space Space Radiation Protection, Space Weather and ExplorationWeather and Exploration

25 April 201225 April 2012

11Kerry LeeKerry Lee

22J. Barzilla , J. Barzilla , 22T. Bevill, T. Bevill, 22A. Dunegan, A. Dunegan, 11D. Fry, D. Fry, 22R. Gaza, R. Gaza, 2 2A.S. Johnson, A.S. Johnson, 22J. Keller, J. Keller, 22M. Langford, M. Langford, 2 2T. T. Lin, Lin, 22N. Stoffle, N. Stoffle, 22A. Welton and A. Welton and 11N. ZappN. Zapp

11NASA Johnson Space Center, SF2, Houston, TX 77058 U.S.A.NASA Johnson Space Center, SF2, Houston, TX 77058 U.S.A.22Lockheed-Martin Space Operations, Houston, TX 77258 U.S.A.Lockheed-Martin Space Operations, Houston, TX 77258 U.S.A.

OVERVIEWOVERVIEW

OperationsOperations

MeasurementsMeasurements

DesignDesign

AnalysisAnalysis

Space WeatherSpace Weather

StatusStatus

OperationsOperations

SRAG, est. 1962SRAG, est. 1962 Real-time console operationsReal-time console operations Crew, ambient monitoringCrew, ambient monitoring Pre-flight planningPre-flight planning Design evaluationsDesign evaluations

Radiation Health OfficeRadiation Health Office InterpretationInterpretation Record KeepingRecord Keeping Risk EstimationRisk Estimation Crew SelectionCrew Selection

Space Medicine Division

Radiation Monitoring for Crew and Space Radiation Monitoring for Crew and Space VehicleVehicle

Active Radiation Detectors Tissue Equivalent Proportional Counter (TEPC) Charge Particle Directional Spectrometer (CPDS) Intra-Vehicular TEPC( IV-TEPC)

Passive Radiation Detectors Crew Passive Dosimeter (CPD) ISS Radiation Area Monitor (RAM) Dosimeter

Console Operations Support 24 hours Contingency Support 4 hour/day Nominal Support

STS-116: Example ProgressionSTS-116: Example Progression

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STS-116 Launch EVA 1 EgressEVA 2 Egress

Probability?Probability?

ISS Expd. 22-25/20A RAM Measured Dose ISS Expd. 22-25/20A RAM Measured Dose RatesRates

High absorbed dose rates: Lab window, SM Crew Quarters

Low absorbed dose rates: Node 2 Crew Quarters, SM-339 (behind treadmil)

0 2 4 6 8 10 12 14 16 18 20 22 24 260

40

80

120

160

200

240

280

320

360

400

SM_P327

ISS Expedition 22-25/20A (02/08/10-03/09/11; 354.3 km)

NODE2 CQ

LAB windowSM CQ

Node 1 SM Lab Airlock Node 2 Columbus Kibo TEPC

Mea

sure

d D

ose

(G

y/da

y

ISS RAM Locations

0 2 4 6 8 10 12 14 16 18 20 22 24 260

40

80

120

160

200

240

280

320

360

400ISS Expedition 20-2J/A (07/15/09-02/22/10; 351.1 km)

NODE2 CQ

LAB windowSM CQ

LAB CQ

Node 1 SM Lab Airlock Node 2 Columbus Kibo TEPC

Me

asu

red

Do

se (G

y/d

ay

ISS RAM Locations

ISS TEPC Measurement During 2012 ISS TEPC Measurement During 2012 March SPEMarch SPE

SAA Passes

Design and AnalysisDesign and Analysis

Exposure PredictionExposure Prediction

Radiation TransportParticle Transport through

Materials

Radiation TransportParticle Transport through

Materials

ShieldingCAD Models – As-built or

Design

ShieldingCAD Models – As-built or

Design

EnvironmentParticle spectrum

(SPE/GCR)

EnvironmentParticle spectrum

(SPE/GCR)

UncertaintiesFuture Environment*Biological Impacts

*Vehicle Design Details

Transport Physics

UncertaintiesFuture Environment*Biological Impacts

*Vehicle Design Details

Transport Physics

Vehicle/Habitat Radiation Exposure AnalysisVehicle/Habitat Radiation Exposure Analysis

ISS Radiation Shielding AnalysisISS Radiation Shielding Analysis

ISS Radiation Shielding AnalysisISS Radiation Shielding Analysis

Orion Crew Exploration Vehicle Design Orion Crew Exploration Vehicle Design AnalysisAnalysis

Modified ISS US Lab DesignModified ISS US Lab Design

Deep Space Habitat “stack”Deep Space Habitat “stack”

Deep Space Habitat Shielding AnalysisDeep Space Habitat Shielding Analysis

Effective Dose Depth Curves for Aluminum Effective Dose Depth Curves for Aluminum and Polyethylene Shieldsand Polyethylene Shields

Space WeatherSpace Weather

Space Weather ForecastingSpace Weather Forecasting

Historical database for Historical database for identification of event identification of event trending/characteristicstrending/characteristics

Probabilistic modeling for Probabilistic modeling for operational mission planningoperational mission planning

ISEP: integration of probabilistic ISEP: integration of probabilistic spectral and SEP dose modelingspectral and SEP dose modeling

Dose projection for in-event risk Dose projection for in-event risk mitigationmitigation

Forecasting of event onset and Forecasting of event onset and impact outside of low-earth orbit. impact outside of low-earth orbit.

MAG4 Model

David Falconer University of Alabama

Future Space Weather Ops

Ensure Data Availability

Develop Forecasting Capability

All-Clear Forecasting Workshop

Subcontract Predictive Tool Development

Assess current state of forecasting models and

input data needs.Data Stream Development

Data Requirements

HEOMD/SMD/OCE Involvement

(SRWG)

Two-Fold ConsiderationTwo-Fold Consideration

1919

Operational Tool DevelopmentOperational Tool Development

Assess model capability:Assess model capability: historical event databasehistorical event database

No single-model solutionNo single-model solution

Highly complex environment:Highly complex environment: Multiple toolsMultiple tools

Bottom Line: Forecasting tools require input data. Ties forecasting ability to asset viability – agency level problem: SMD/ESMD/SMD/OCE 2020

StatusStatusCurrent and Future WorkCurrent and Future Work

IV-TEPC is an updated version of the existing TEPC with similar capability in terms IV-TEPC is an updated version of the existing TEPC with similar capability in terms of operation and data types. of operation and data types.

Activated on orbit on April 23, 2012Activated on orbit on April 23, 2012. First data being analyzed now.. First data being analyzed now. Two Two omni-directionalomni-directional detectors attached to the spectrometer housing detectors attached to the spectrometer housing Provides continuous real-time data and also stores data locallyProvides continuous real-time data and also stores data locally Relocated about every 4 weeksRelocated about every 4 weeks Requires power and data connectionsRequires power and data connections Alarm threshold set at 5mrad/min (no local alarm - C&W system Alarm threshold set at 5mrad/min (no local alarm - C&W system only)only)

IV-TEPCIV-TEPC

Radiation Environment Monitor (REM)Radiation Environment Monitor (REM)

The Timepix Detector Developed as a High Energy Developed as a High Energy

Physics application of medical Physics application of medical imaging technologyimaging technology

Hybrid Pixel Detector with Hybrid Pixel Detector with independent counting and independent counting and readout circuitry in each pixel readout circuitry in each pixel footprintfootprint

256 x 256 pixel grid with total 256 x 256 pixel grid with total area of 2 cm2area of 2 cm2

Time Over Threshold mode Time Over Threshold mode coupled with calibration allows coupled with calibration allows measurement of energy measurement of energy deposited per pixeldeposited per pixel

Pixel Detector Image from Medipix collaboration website: http://medipix.web.cern.ch/medipix/img/medipix2/web_flipchip.gif

Pixel Detector Technology

ISS Radiation Assessment Detector (RAD)ISS Radiation Assessment Detector (RAD)

RIB(New for ISS)

FND(New for ISS)RSH

(MSL Heritage)

5.64"

11

.75

"

14.4"Weight = 24 lbs

RAD Sensor HeadFast Neutron Detector

RAD Interface Board

Designed to measure neutrons Designed to measure neutrons and charged particles from and charged particles from protons through Ironprotons through Iron

Contains CPDS-like detector Contains CPDS-like detector stackstack

Will provide real-time data Will provide real-time data Can be relocated within the Can be relocated within the

habitable volumehabitable volume Currently in development Currently in development

based on the MSL-RAD based on the MSL-RAD instrumentinstrument

Advanced Radiation Protection ProjectAdvanced Radiation Protection Project

MC-CAD: Radiation protection design through analysis of complex MC-CAD: Radiation protection design through analysis of complex CAD geometries using Monte Carlo radiation transport codes. CAD geometries using Monte Carlo radiation transport codes.

ISEP: The Integrated Solar Energetic Proton Event Alert Warning ISEP: The Integrated Solar Energetic Proton Event Alert Warning System. Collaboration with JSC/GSFC/MSFC/LaRC/Univ. System. Collaboration with JSC/GSFC/MSFC/LaRC/Univ. Alabama/Univ. Tenn.Alabama/Univ. Tenn.

Both tasks are underway with expected operational products Both tasks are underway with expected operational products completed in Sept. 2014completed in Sept. 2014

Technology DevelopmentTechnology Development

Active ShieldingActive Shielding Research to determine if it is mass and/or power prohibitive Research to determine if it is mass and/or power prohibitive Technology development on system components that will improve Technology development on system components that will improve

shielding effectiveness and decrease mass and power needsshielding effectiveness and decrease mass and power needs Measurements Measurements

ISS Detailed Test Objective – REMs starting this summerISS Detailed Test Objective – REMs starting this summer Exploration Flight Test 1(EFT-1) (RAMs and REMs) – 2014 Exploration Flight Test 1(EFT-1) (RAMs and REMs) – 2014 Radiation Assessment Detector (RAD) with an added fast neutron Radiation Assessment Detector (RAD) with an added fast neutron

detector channel – 2015 detector channel – 2015

SummarySummary

For long duration exploration missions (>6 months) new shielding For long duration exploration missions (>6 months) new shielding solutions are needed to meet current NASA radiation risk limitssolutions are needed to meet current NASA radiation risk limits

Progressively reducing mass and power requirements for radiation Progressively reducing mass and power requirements for radiation monitoring hardwaremonitoring hardware

Collaborating to develop space weather forecasting tools for future Collaborating to develop space weather forecasting tools for future human exploration missionshuman exploration missions

CAD design tool development to aide in space vehicle design to CAD design tool development to aide in space vehicle design to minimize parasitic shielding mass through analysis during vehicle minimize parasitic shielding mass through analysis during vehicle design processdesign process