Spacecraft Radiation Protection
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Spacecraft Radiation Protection Course Sampler

Spacecraft Radiation Protection Course Sampler

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  • http://www.ATIcourses.com/schedule.htm http://www.aticourses.comspacecraft_radiation_protection.htm ATI Course Schedule: ATI's Spacecraft Radiation: Professional Development Short Course On: Spacecraft Radiation Protection Instructor: Dr. Alan C. Tribble
  • Spacecraft Radiation Protection Summary This two-day course provides an in-depth overview of risks posed by radiation to spacecraft and working solutions minimizing those risks. Students will gain a solid understanding of the radiation environment, its measurement, its effects and effective mitigation strategies. Course Outline 1. Space Radiation Environment. Trapped protons and electrons. Solar energetic particles. Cosmic rays. Neutrons and gamma rays from Radioactive Thermoelectric Generators (RTGs). Secondary neutrons from large space structures. Mars surface and high altitude Earth enironment. 2. Total Dose and Effects. Energy per unit mass. Units--rads, REMs, Grey, Sieverts. Ionization effects. Charge deposition, migration and collection. Effects on digital and analog MOS and bipolar devices including ELDRS. Annealing, recovery, rebound. 3. Displacement Damage. Crystalline lattice deformations. Damage thresholds in silicon and gallium arsenide. Damage equivalence and NIEL. Effects of protons and neutrons on solar cells and detectors such as CCDs. Dark current, charge transfer efficiency, maximum power degradation. 4. Single Event Effects. Ionization by primary particles and secondaries from nuclear collisions. Charge collection in small structures. Effects in digital and analog devices. Transient and permanent upsets, soft errors, latch-up, burn-out, SEFI. Volatile and non-volatile memories, micro and signal processors, DC/DC converters, optoelectronics. 5. Testing and Mitigation Techniques. Total dose testing. SEE testing. Facilities. Shielding. Derating. Conservative circuit design. Systems mitigation. EDAC, latch-up protection circuitry, watch dog timers, autonomy. 6. Human Effects. Long duration exposure in low Earth orbit and interplanetary transport vehicles. Threat of high-energy neutrons to astronauts. Effects in tissue and organs. Dose Equivalent and weighting factors. Risk of carcinogenesis, DNA damage. CNS effects Instructor Dr. Alan C. Tribble has provided space environments effects analysis to more than one dozen NASA, DoD, and commercial programs, including the International Space Station, the Global Positioning System (GPS) satellites, and survival surveillance spacecraft. He holds a Ph.D. in Physics from the University of Iowa and has been twice a Principal Investigator for the NASA Space Environments and Effects Program. He is the author of four books, including the course text: The Space Environment - Implications for Space Design, and over 20 additional technical publications. He is an Associate Editor of the Journal of Spacecraft and Rockets, and Associate Fellow of the AIAA and a Senior Member of the IEEE. Dr. Tribble recently won the 2008 AIAA James A. Van Allen Space Environments Award. He has taught a variety of classes at the University of Southern California, California State University Long Beach, the University of Iowa, and has been teaching courses on space environments and effects since 1992 What You Will Learn • What the models are for space environments, where to find them, how to use them. • What the common radiation units mean. • How to equate damage from different species of radiation. • How to conduct total dose test. • How to conduct SEE tests. • How to use dose-depth curves in determining shield thickness. • How to shield neutrons. Applied Technology Institute 349 Berkshire Drive Riva, MD 21140 410-956-8805 / 888-501-2100 Fax: 410-956-5785 www.ATIcourses.com
  • www.ATIcourses.com Boost Your Skills with On-Site Courses Tailored to Your Needs The Applied Technology Institute specializes in training programs for technical professionals. Our courses keep you current in the state-of-the-art technology that is essential to keep your company on the cutting edge in today’s highly competitive marketplace. Since 1984, ATI has earned the trust of training departments nationwide, and has presented on-site training at the major Navy, Air Force and NASA centers, and for a large number of contractors. Our training increases effectiveness and productivity. Learn from the proven best. For a Free On-Site Quote Visit Us At: http://www.ATIcourses.com/free_onsite_quote.asp For Our Current Public Course Schedule Go To: http://www.ATIcourses.com/schedule.htm 349 Berkshire Drive Riva, Maryland 21140 Telephone 1-888-501-2100 / (410) 965-8805 Fax (410) 956-5785 Email: ATI@ATIcourses.com
  • Sampler 2009 Slide #2 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com COURSE OBJECTIVE • The purpose of this course is to characterize space (and atmospheric) radiation effects and how they are mitigated – By the end of class, you should be able to read and follow most papers and presentations in radiation effects and know where to look for further expertise
  • Sampler 2009 Slide #3 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com ABOUT THE INSTRUCTOR • Dr. Alan Tribble – Over Twenty Years Experience in Space Environments and Effects • Author of First Text on Space Environments & Effects • Principal Investigator for the NASA Space Environments & Effects Program • Associate Editor for the AIAA Journal of Spacecraft and Rockets • Instructor for Space Environments & Effects Courses Since 1992 – Winner of the 2008 AIAA James A. Van Allen Award • Presented to recognize outstanding contributions to space and planetary environment knowledge and interactions as applied to the advancement of aeronautics and astronautics.
  • Sampler 2009 Slide #4 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com THE ENVIRONMENTS OF SPACE • Vacuum Environment Effects – Phenomena Associated With the Absence of a Substantial Atmosphere • Neutral Environment Effects – Phenomena Associated With the Presence of a Tenuous Neutral Atmosphere • Plasma Environment Effects – Phenomena Associated With the Presence of Low Energy (KeV Range) Charged Particles • Radiation Environment Effects – Phenomena Associated With the Presence of High Energy (MeV - GeV Range) Particles / Photons • Micrometeoroid / Orbital Debris Effects – Phenomena Associated With the Presence of Hypervelocity Particles
  • Sampler 2009 Slide #5 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com RADIATION ANOMALIES
  • Sampler 2009 Slide #6 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com IMPACT DURATION
  • Sampler 2009 Slide #7 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com FUNDAMENTAL FORCES • Four Forces – Strong Nuclear • Important Near the Nucleus – Weak Nuclear • Important Near the Nucleus – Electrical • Very Significant for Particles That are Charged – Gravitational • Only Important for Very Large Masses Nuclear Forces Only Dominates Near the Nucleus Electrical Force Always Dominates Outside the Nucleus
  • Sampler 2009 Slide #8 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com STOPPING POWER http://en.wikipedia.org/wiki/Stopping_power_(particle_radiation)
  • Sampler 2009 Slide #9 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com BRAGG PEAK http://en.wikipedia.org/wiki/Stopping_power_(particle_radiation)
  • Sampler 2009 Slide #10 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com LET VS RANGE
  • Sampler 2009 Slide #11 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com Photon Energy (MeV) AbsorptionCoefficient(cm^2/g) 0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2 0.1 1 10 100 Compton Pair Production Photoelectric Total 10-1 100 101 102 Cross Section (cm2 /g) PHOTON CROSS SECTION
  • Sampler 2009 Slide #12 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com ATMOSPHERIC NEUTRONS • The Neutron Flux is a Function of Altitude and Latitude • The Worst Location is a Polar Route at About 55,000 Feet Neutron Flux vs Altitude 0 0.2 0.4 0.6 0.8 1 1.2 1.4 0 20 40 60 80 100 Altitude (Thousand Feet) Flux(n/cm^2s) Neutron Flux vs Latitude 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 0 20 40 60 80 100 Latitude (Deg.) Flux(n/cm^2s) Normand, E., and Baker, T. J., “Altitude and Latitude Variations in Avionics SEU and Atmospheric Neutron Flux,” IEEE Tns. Nuc. Sci., Vol. 40, No. 6, pp. 1484 - 1490, December 1993.
  • Sampler 2009 Slide #13 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com EFFECTS OF INTERACTIONS • Main Effects – Ionization (~ 99%) • Ionizing Target Atoms Produces More Charge Carriers – Displacement (~1%) • Lattice Atoms are Rearranged – Absorption / Capture (< 1%) • Target Nucleus May Absorb Radiation and Re-Emit Other Particles • Result – Electrical and Chemical Properties of the Target are Altered
  • Sampler 2009 Slide #14 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com MEASURES OF ENERGY DEPOSITION • Total Ionizing Dose (TID) – A Measure of the Amount of Energy Lost Due to Ionizations – TID is a Function of • The Radiation – Energy and Type • The Target Material • Displacement Damage (DD) – A Measure of the Amount of Energy Lost Due to Displacements – DD is a Function of • The Radiation – Energy and Type • The Target Material
  • Sampler 2009 Slide #15 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com MEASURES OF ENERGY LOSS / PATH • Linear Energy Transfer (LET) – Measures the Amount of Energy Lost Per Unit Path Length Due to Ionizations • Non-Ionizing Energy Loss (NIEL) – Measures the Amount of Energy Loss Per Unit Path Length Due to Displacements
  • Sampler 2009 Slide #16 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com AREA OF REFLECTION GEOLEO Particle Motion Trapping Moves Particles North - South Drifts Move Particles East-West MAGNETIC TRAPPING OF THE RADIATION BELTS GPS
  • Sampler 2009 Slide #17 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com GOES SATELLITE ENVIRONMENT DATA
  • Sampler 2009 Slide #18 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com • Magnetic Field Lines Entering the Atmosphere at High Latitudes Allow Charged Particles to Reach Lower Altitudes in Polar Regions • Consequently, the Radiation Dose and Dose Rate are Increased in Polar Orbits – An Example of This is the Aurora Borealis and the Aurora Australialis POLAR VS EQUATORIAL
  • Sampler 2009 Slide #19 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com • A Decrease in the Dipole Term of the Earth’s Magnetic Field Results in a Westward and Southward Drift of the Ground-Level Local Minimum in the Magnetic Field Known as the South Atlantic Anomaly (SAA) • This Allows Higher Energy Particles to Reach Lower Altitudes Over the South Atlantic SOUTH ATLANTIC ANOMALY - 1
  • Sampler 2009 Slide #20 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com SOUTH ATLANTIC ANOMALY - 2
  • Sampler 2009 Slide #21 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com Single Event Effects Often Maximize Over The SAA SEU FOR ALEXIS SPACECRAFT
  • Sampler 2009 Slide #22 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com SPE COMPOSITION Large Solar Proton Event Spectra at 1 AU 1.00E+07 1.00E+08 1.00E+09 1.00E+10 1.00E+11 1 10 100 1000 Kinetic Energy (MeV) IntegralFluence,(protons/ cm^2) Feb 1956 Nov 1960 Aug 1972 Aug 1989 Sep 1989 Oct 1989 Wilson, J. W., Cucinotta, F. A., Simonsen, L. C., Shinn, J. L., Thibeault, S. A., and Kim, M. Y., "Galactic and Cosmic Ray Shielding in Deep Space", NASA TP 3682, December 1997
  • Sampler 2009 Slide #23 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com GCR COMPOSITION Galactic Cosmic Ray Fluence, Solar Max (1981) 1.00E-06 1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+00 1.00E+01 1.00E+02 1.00E+03 1.00E+04 1.00E+05 1.00E+06 1.00E-01 1.00E+00 1.00E+01 1.00E+02 1.00E+03 1.00E+04 1.00E+05 1.00E+06 Kinetic Energy (A MeV) AnnualFluence,(particles/cm^2-AMeV) Z = 1 Z = 2 Z: 3 - 10 Z: 11 - 20 Z: 21 - 28 Wilson, J. W., Cucinotta, F. A., Simonsen, L. C., Shinn, J. L., Thibeault, S. A., and Kim, M. Y., "Galactic and Cosmic Ray Shielding in Deep Space", NASA TP 3682, December 1997
  • Sampler 2009 Slide #24 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com MITIGATION TECHNIQUES • Shielding – Prevent the Radiation Environment From Reaching the Crew or Sensitive Electronics • Not Effective on Very Energetic (GeV) Charged Particles • Parts Selection – Choose Parts or Materials That Can Withstand the Total Dose Environment Anticipated – Choose Parts That are Immune or Resistant to SEE • Fault Tolerance – Hardware • Redundancy, Majority Voting, … – Software • Error Detection and Correction (EDAC), Hamming Codes, …
  • Sampler 2009 Slide #25 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com GPS Trapped Radiation: 20,000 km - 55 Deg 1.00E-02 1.00E-01 1.00E+00 1.00E+01 1.00E+04 1.00E+05 1.00E+06 1.00E+07 1.00E+08 1.00E+09 1.00E+10 1.00E+11 1.00E+12 1.00E+13 Fluence (# cm ^-2 day^-1) Energy(MeV) Protons Electrons - Solar Min Electrons - Solar Max 20,000 km @ 55 degrees 104 105 106 107 108 109 1010 1011 1012 1013 Fluence (cm-2 day -1) 101 Energy (MeV) 100 10-1 10-2 Protons Electrons - Solar Min. Electrons - Solar Max. GPS RADIATION ENVIRONMENT
  • Sampler 2009 Slide #26 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com Altitude = 20,000 km Inclination = 55 deg. Shielding = Full-Sphere Shie ld ing Thic kne ss (m ils - Al) Dose(rad/day) 0.10 1.00 10.00 100.00 1000.00 10000.00 10 100 1000 To ta l Pro to n Ele c tro n Bre m s. GPS RADIATION DOSE
  • Sampler 2009 Slide #27 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com DESIGN EXAMPLE: SOLAR ARRAY SIZING • Solar Array Size is Driven by the Amount of Energy That Must be Produced – A = Solar Array Area (m2) – P = Power Required (W) –  = Efficiency • Efficiency is Degraded by Radiation – BOL Value is Greater Than the EOL Value • Efficiency Loss is Minimized by Adding a Transparent Shield – Coverslide – S = Sun’s Power Output (1367 W/m2 at Earth Orbit) S P A  
  • Sampler 2009 Slide #28 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com TOTAL IONIZING DOSE III • Digital Devices – Suffer threshold voltage shifts, supply current increases and timing degradation • Linear Devices – Experience increased input bias currents, offset voltages and offset currents as circuitry becomes unbalanced • In worst cases functionality ceases – Particularly when the timing is affected in a VLSI device and after many nodes information does not reach the next gate in the correct time window.
  • Sampler 2009 Slide #29 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com DISPLACEMENT DAMAGE SKETCH
  • Sampler 2009 Slide #30 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com • An Energetic Particle Passes Through a Semiconductor and Creates a Trail of Ionized Particles in the Vicinity of a Reverse Biased PN Junction – The Sudden Flux in Ionized Particles Can Cause a Swing in Bias Across the Junction – The Change May Alter the State of the Device • This is an Example of a Single Event Effect (SEE) SINGLE EVENT EFFECTS (SEE)
  • Sampler 2009 Slide #31 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com TYPES OF EFFECTS • Single Event Upset – Change in state of a memory element – System-level manifestations depend on application • Single Event Latchup – Low resistance path develops between power and ground through the device, usually destructive – Sometimes observe “mini-latch” behavior • Single Event Functional Interrupt – Upset which places a device in an ill-defined condition – Causes system to lock up or jump into an unknown configuration • Single Event Transient – Spurious voltage spike that can cause system-level effects – Increased noise in the system
  • Sampler 2009 Slide #32 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com TYPES OF EFFECTS • Single Event Burnout – Localized short through power MOSFET – Permanently damages the part • Single Event Gate Rupture – Localized short through drain-to-oxide interface in a power MOSFET – Permanently increases gate leakage • Single Event Dielectric Rupture – Oxide damage in non-volatile elements or anti- fuse type FPGAs
  • Sampler 2009 Slide #33 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com ION STRIKE SCHEMATIC
  • Sampler 2009 Slide #34 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com VIN VOUT p-type substrate n+ n+ n-well p+ p+p+ n+ VSSVDD Source Gate Drain Source SEE ILLUSTRATION Radiation (proton, ion, neutron, …) Upset occurs if channel current turned on Latchup occurs if parasitic current loop initiated
  • Sampler 2009 Slide #35 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com SEU EXAMPLE: SAMSUNG DRAM
  • Sampler 2009 Slide #36 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com TOTAL IONIZING DOSE (TID) TEST FLOW • 25° C anneal – For simulation of reduction in oxide trapped charge • 100° C anneal – For accelerated production of interface trapped charge Irr. To Spec. 50-300 rad/s Pass Elec? Irr. 50% Over 50-300 rad/s Biased Anneal 168 hr @ 100C Pass Elec? Parts OK Reject Parts Yes Yes No Biased Anneal @ 25 C Pass Elec? No No Yes
  • Sampler 2009 Slide #37 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com ELDRS TEST FLOW • May require extensive evaluation Start Review Data ELDRS? TM1019 or other Accept Risk? Initial Test 1) Baseline high rate at room temp 2) Compare to low rate or elev. temp ELDRS? No No ?? Yes Yes 1) Test at 10 mrad/s with margin of 2 or 2) test at 10 rad/s, 100C with margin of 3 Yes 1) Determine max low dose rate enhancement 2) Elevated temperature irradiation and anneal No Acceptance Test
  • Sampler 2009 Slide #38 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com TEST FACILITY REQUIREMENTS
  • Sampler 2009 Slide #39 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com TEST FACILITY REQUIREMENTS
  • Sampler 2009 Slide #40 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com NASA INTERNET SITES • Glenn Research Center – Space Environments and Experiments Branch • http://www.grc.nasa.gov/WWW /epbranch/ • Goddard Space Flight Center – Radiation Effects and Analysis • http://radhome.gsfc.nasa.gov – National Space Science Data Center (NSSDC) • http://nssdc.gsfc.nasa.gov – Community Coordinated Modeling Center (CCMC) • http://ccmc.gsfc.nasa.gov/mod elweb/ • Jet Propulsion Laboratory – Radiation Effects Group • http://parts.jpl.nasa.gov • Johnson Space Center – Orbital Debris Program Office • http://orbitaldebris.jsc.nasa.gov • Langley Research Center – Space Environments and Technology Archive System (SETAS) • http://setas-www.larc.nasa.gov/ • Marshall Space Flight Center – Space Environments and Effects Program • http://see.msfc.nasa.gov
  • Sampler 2009 Slide #41 Applied Technology Institute (ATI) www.aticourses.com Copyright Dr. Alan Tribble. Do Not Reproduce Without Permission. www.atribble.com OTHER INTERNET SITES • NOAA – Space Weather Prediction Center • http://www.swpc.noaa.gov • Space Weather – Science News and Information • http://www.spaceweather.com – Space Science Institute • http://www.spaceweathercente r.org/ • Space Environment Information System (SPENVIS) – interface to models of the space environment and its effects, including the natural radiation belts, solar energetic particles, cosmic rays, plasmas, gases, and "micro-particles". • www.spenvis.oma.be • Instructor’s Web Site – Links to Site’s of Interest • http://www.atribble.com
  • You have enjoyed an ATI's preview of http://www.aticourses.com/wordpress-2.7/weblog1/ Please post your comments and questions to our blog: Sign-up for ATI's monthly Course Schedule Updates : http://www.aticourses.com/email_signup_page.html Spacecraft Radiation Protection