Radiation Physiology and Effectsspacecraft.ssl.umd.edu/.../697S13/697S13L06.radiation1.pdf · 2013....
Transcript of Radiation Physiology and Effectsspacecraft.ssl.umd.edu/.../697S13/697S13L06.radiation1.pdf · 2013....
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Radiation Physiology and Effects• Sources and types of space radiation• Effects of radiation• Shielding approaches
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© 2011 David L. Akin - All rights reservedhttp://spacecraft.ssl.umd.edu
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
The Origin of a Class X1 Solar Flare
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
The Earth’s Magnetic Field
Ref: V. L. Pisacane and R. C. Moore, Fundamentals of Space Systems Oxford University Press, 1994
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
The Van Allen Radiation Belts
Ref: V. L. Pisacane and R. C. Moore, Fundamentals of Space Systems Oxford University Press, 1994
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Cross-section of Van Allen Radiation Belts
Ref: V. L. Pisacane and R. C. Moore, Fundamentals of Space Systems Oxford University Press, 1994
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Electron Flux in Low Earth Orbit
Ref: V. L. Pisacane and R. C. Moore, Fundamentals of Space Systems Oxford University Press, 1994
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Heavy Ion Flux
Ref: Neville J. Barter, ed., TRW Space Data, TRW Space and Electronics Group, 1999
Background Solar Flare
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Radiation Units• Dose D= absorbed radiation
• Dose equivalent H= effective absorbed radiation
• LET = Linear Energy Transfer <KeV/µ m>
8
1 Gray = 1Joule
kg= 100 rad = 10, 000
ergs
gm
1 Sievert = 1Joule
kg= 100 rem = 10, 000
ergs
gm
H = DQ rem = RBE × rad
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Radiation Quality Factor
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Radiation QX-rays 1
5 MeV !-rays 0.51 MeV !-rays 0.7
200 KeV !-rays 1.0Electrons 1.0Protons 2-10
Neutrons 2-10"-particles 10-20
GCR 20+
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Radiation in Free Space
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Radiation Dose vs. Orbital Altitude
Ref: Neville J. Barter, ed., TRW Space Data, TRW Space and Electronics Group, 1999
300 mil (7.6 mm) Al shielding
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Dosage Rates from Oct/Nov 2003 SPE
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
SPEs in Solar Cycles 19, 20, and 21
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
GCR Constituent Species
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Solar Max/Min GCR Proton Flux Ratio
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Radiation Damage to DNA
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Symptomology of Acute Radiation Exposure• “Radiation sickness”: headache, dizziness, malaise,
nausea, vomiting, diarrhea, lowered RBC and WBC counts, irritability, insomnia
• 50 rem (0.5 Sv)– Mild symptoms, mostly on first day– ~100% survival
• 100-200 rem (1-2 Sv)– Increase in severity and duration– 70% incidence of vomiting at 200 rem– 25%-35% drop in blood cell production– Mild bleeding, fever, and infection in 4-5 weeks
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Symptomology of Acute Radiation Exposure• 200-350 rem (2-3.5 Sv)
– Earlier and more severe symptoms– Moderate bleeding, fever, infection, and diarrhea at 4-5
weeks• 350-550 rem (3.5-5.5 Sv)
– Severe symptoms– Severe and prolonged vomiting - electrolyte imbalances– 50-90% mortality from damage to hematopoietic system if
untreated
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Symptomology of Acute Radiation Exposure• 550-750 rem (5.5-7.5 Sv)
– Severe vomiting and nausea on first day– Total destruction of blood-forming organs– Untreated survival time 2-3 weeks
• 750-1000 rem (7.5-10 Sv)– Survival time ~2 weeks– Severe nausea and vomiting over first three days– 75% prostrate by end of first week
• 1000-2000 rem (10-20 Sv)– Severe nausea and vomiting in 30 minutes
• 4500 rem (45 Sv)– Survival time as short as 32 hrs - 100% in one week
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Long-Term Effects of Radiation Exposure
• Radiation carcinogenesis– Function of exposure, dosage, LET of radiation
• Radiation mutagenesis– Mutations in offspring– Mouse experiments show doubling in mutation rate at
15-30 rad (acute), 100 rad (chronic) exposures
• Radiation-induced cataracts– Observed correlation at 200 rad (acute), 550 rad (chronic)– Evidence of low onset (25 rad) at high LET
20
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Radiation Carcinogenesis• Manifestations
– Myelocytic leukemia– Cancer of breast, lung, thyroid, and bowel
• Latency in atomic bomb survivors– Leukemia: mean 14 yrs, range 5-20 years– All other cancers: mean 25 years
• Overall marginal cancer risk– 70-165 deaths/million people/rem/year– 100,000 people exposed to 10 rem (acute) -> 800
additional deaths (20,000 natural cancer deaths) - 4%
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Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
NASA Radiation Dose Limits
22
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Density of Common Shielding Materials
23
0
2
4
6
8
10
12
Polyethyle
neWate
rGr/E
p
Acrylic
s
AluminumLea
d
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Comparative Thickness of Shields (Al=1)
24
0
1
2
3
Polyethyle
neWate
rGr/E
p
Acrylic
s
AluminumLea
d
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Comparative Mass for Shielding (Al=1)
25
0
1
2
3
4
5
Polyeth
ylene
Water
Gr/Ep
Acrylics
Aluminu
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ad
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Effective Dose Based on Shielding
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Francis A. Cucinotta, Myung-Hee Y. Kim, and Lei Ren, Managing Lunar and Mars Mission Radiation Risks Part I: Cancer Risks, Uncertainties, and Shielding Effectiveness NASA/TP-2005-213164, July, 2005
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Shielding Materials Effect on GCR
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–, Human Integration Design Handbook, NASA SP-2010-3407, Jan. 2010
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Lunar Regolith Shielding for SPE
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–, Human Integration Design Handbook, NASA SP-2010-3407, Jan. 2010
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Mars Regolith Shielding Effectiveness
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–, Human Integration Design Handbook, NASA SP-2010-3407, Jan. 2010
Radiation Physiology and EffectsENAE 697 - Space Human Factors and Life Support
U N I V E R S I T Y O FMARYLAND
Radiation Exposure Induced Deaths
30
Francis A. Cucinotta, Myung-Hee Y. Kim, and Lei Ren, Managing Lunar and Mars Mission Radiation Risks Part I: Cancer Risks, Uncertainties, and Shielding Effectiveness NASA/TP-2005-213164, July, 2005
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• ^)0)%.)%,)'$9'*2-Q'$%'.$-)@*"3)-'2%'-0",)'– c2$&$EF'$9'*)0"2*J',)&&'p'#--+)'*)E+&"#$%'
• =*).2,#%E'-$&"*')G)%3-'– q)10$*"&'"%.'-2S)'0*).2,#$%-'
• :;3*"0$&"#$%'9*$1');0)*21)%3"&'."3"'3$'6+1"%-'• ?%.2G2.+"&'*".2"#$%@-)%-2#G23F'– M)%)#,J'.2)3"*F'"%.'“6)"&36F'7$*Q)*”')P),3-'
^+*"%3)'p'N+,2%$r"J'!"3+*)'8)G]'N"%,)*'BDkksC'
(%) Fatal Cancer Risk0 3 6 9 12 15
Probab
ility
0.000
0.003
0.006
0.009
0.012
0.015
Distribution aluminumDistribution polyethyleneDistribution Liq. Hydrogen (H2) E(alum) = 0.87 Sv E(poly) = 0.77 SvE(H2) = 0.43 SvR(alum) = 3.2 [1.0,10.5] (%)R(poly) = 2.9 [0.94, 9.2] (%)R(H2) = 1.6 [0.52, 5.1] (%)
N+,2%$r"')3'"&'8".2"3'X)"-'BDkk\C'
4D'
/0",)'8".2"#$%'/62)&.2%E'2-'5)&&'t%.)*-3$$.'
8".2"#$%'/62)&.2%E'X"3)*2"&-'
),I,(:!<]d>!0CM!$%4!S+A!0-E$#!;'%!
Shielding Depth, g/cm20 5 10 15 20 25 30 35
Dose
Equ
ivalen
t, rem
/yr1
10
100
1000
10000GCR L. HydrogenGCR PolyethyleneGCR GraphiteGCR AluminumGCR RegolithSPE GraphiteSPE RegolithSPE L. Hydrogen
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