Extended Lunar Outpost
Titanium-Based
Radiation Shielding
Lunar Knights
Team Members
Luke Richards: Team Leader
Trevor Morris: Team Contact and Professional Manager
Henry Swider: Lead Writer and Editor
Scott Wiedemann: Computer Design Specialist
Aaron Totsch: Systems and Support Expert
Project Background
NASA has requested
designs for lunar
radiation protection
mechanisms
Without radiation
protection, long-term
missions are too
dangerous
Figure 1
Project Constraints
The radiation protection
mechanisms must be
durable and effective
The mechanisms will not
use regolith as a radiation
barrier
Project cost and current
technology do not limit
the designs
Figure 2
Design Evaluation Criteria
Plausibility – the overall feasibility of the solution
Cost – the amount of money required to implement a solution
Effectiveness – how well the solution will work
Implementation time – the time required to set up the solution
and have it working
Longevity – the amount of time that the solution will last
Earth resource dependency – the amount of resources that
must be transported from Earth
Ease of material transportation – reasonability of moving the
required materials
Durability – the strength and toughness of the solution
Titanium Shielding on the Moon
Titanium deposits on the
moon
Areas of high concentration
Within red and yellow
volcanic glasses
Easily melted
Refined and used as shield in
lunar outposts
Blocks and scatters smallwave electromagnetic waves
Figure 3
Figure 4
Geologic Significance
There are many reasons to choose the
Aristarchus plateau as an outpost point
Many materials and resources contained within
the regolith
Important geological areas located nearby the
plateau
Aristarchus Crater and Surrounding Areas
Figure 5
Lunar Outpost
Figure 6
Very flat landing site
Not much debris
No extreme elevation
changes
Ilmenite Content
High concentrations of
ilmenite (FeTiO3) and
glass volcanic beads
Magenta color is high in
ilmenite
Mostly located in
Schroter’s Valley
Figure 7
Figure 8
Schroter’s Valley
Figure 9
Deep valley provides
protection from erosive
forces
Very old basalts within
the valley
High ilmenite and
volcanic bead
concentrations
Gruithuisen Domes
Northeast of Aristarchus
plateau
Unknown composition
Strong evidence points
to a volcanic origin
Area for further study
Figure 10
Lichtenberg Crater
Very young basalts
extracted by impact
Darkened rays suggest an
older crater, but the
crater is very fresh
Dark rays due to
composition, not age.
Figure 11
Radiation
Primary Hazards to Lunar Outpost
Solar Flares
Galactic Cosmic Rays (Cosmic Radiation)
Current Knowledge
Future Missions
Damage from Radiation
Solar Flares
Coronal Mass Ejecta
Release high-energy
protons
X-rays and other
wavelengths of radiation
Figure 12
Cosmic Radiation
Figure 13
Apollo Mission Radiation Levels
First information on radiation in space
Absolute not relative radiation levels
Table 1
Phantom Torso
Onboard International
Space Station
Polymer that simulates
human tissue
300 radiation sensors at
varying depths
Figure 14
Radiation Levels on ISS
Galactic Cosmic Rays comprised 80 % of radiation
Table 2
Types of Radiation Quality Factor (QF)
x or gamma rays
1
beta particles
1
neutrons and protons of unknown
energy
10
singly charged particles of
unknown energy with rest mass
greater then 1 amu
10
alpha particles
20
particles of multiple or unknown
charge of unknown energy
20
Future Missions
Lunar Reconnaissance Orbiter
Cosmic Ray Telescope for the Effects of Radiation
Figure 15
Radiation Damage in DNA
Figure 16
Titanium Physical
Specifications
Resilient to Lunar
Impacts
Figure 17
Micrometeorite Impacts
Dust Plumes
High Strength-Weight
Ratio
Mechanical Properties
Typical Physical and Mechanical
Properties of Titania
Table 3
Density
Porosity
Modulus of Rupture
Compressive Strength
Poisson’s Ratio
Fracture Toughness
Shear Modulus
Modulus of Elasticity
Microhardness (HV0.5)
Resistivity (25°C)
Resistivity (700°C)
Dielectric Constant (1MHz)
Dissipation factor (1MHz)
Dielectric strength
Thermal expansion (RT-1000°C)
Thermal Conductivity (25°C)
4 gcm-3
0%
140MPa
680MPa
0.27
3.2 Mpa.m-1/2
90GPa
230GPa
880
1012 ohm.cm
2.5x104 ohm.cm
85
5x10-4
4 kVmm-1
9 x 10-6
11.7 WmK-1
Titanium Shielding
Properties
Low Density Metal
Molecular Cross-Section
Protects from short wave
Galactic Cosmic Rays
Small nucleus prevents
scattering
Absorbs large wave
radiation
Titanium Dioxide
Alloys
Figure 18
Lunar Titanium Gathering
Obtain from lunar surface using excavators
Bucket excavator design
Figure 19
Lunar Titanium Gathering
Raw material transportation infrastructure
Figure 20
Titanium Transporting & Refining
Figure 21
Titanium Refining Facility
Figure 22
Kroll Process for Titanium Refining
Ore is
converted to
titanium sponge
Common
titanium
refining process
on Earth
Figure 23
Titanium Refining
Plasma reaction with radio frequency-generated
hydrogen plasma
Formation of water and metal compounds
Oxygen used for life support systems
Figure 24
Architecture Specifications
Shield must protect astronauts and equipment for
extended stays
Able to withstand high doses of radiation like solar
wind and cosmic radiation
Shield must be durable enough to withstand abnormal
increases in micrometeorite impacts and solar weather
Lead is preferred material on Earth, but has structural
disadvantages
Titanium alloys are very strong and durable which is
ideal for the outpost
Architecture Specifications
Tin can architecture can easily integrate our shield
Titanium dioxide is an effective exterior radiation shield
as well as a structural material
Titanium offers a high strength per unit weight
Titanium shell will protect entire outpost
Thickness of shield will depend on the concentrations
of the titanium and titanium dioxide
Estimated that shield will be over 4.5 inches thick
Tin-Can Outpost
Figure 25
Architecture Specifications
The titanium will add support to the exterior
with minimal added mass
Many lunar outposts could be outfitted with a
titanium shield architecture
Amount and composition of titanium dioxide is
dependant on construction of outpost
No cost associated with the design
Architecture Specifications
Byproducts like aluminum could be used for an
internal structural material
Titanium on Earth is a very expensive building
material
Sectional View
Figure 26
Conclusion
Titanium is a very effective design
Not dependant on Earth resources
Strong, durable, and protects against radiation
Figure Citations
Figure 1 – http://lunar.arc.nasa.gov/results/neures.htm
Figure 2 – http://www.nagc.org/uploadedImages/astronaut.jpg
Figure 3 – http://www.psrd.hawaii.edu/Dec00/highTi.html
Figure 4 – http://www.chemsoc.org/chembytes/ezine/images/2001/woodruff_jul01_img.gif
Figure 5 – http://www.lpi.usra.edu/meetings/lpsc2008/pdf/2534.pdf
Figure 7– http://hubblesite.org/newscenter/archive/releases/2005/29/image/b/format/web_print/
Figure 6 – http://www.hq.nasa.gov/office/pao/History/alsj/a15/AS15-88-12005.jpg
Figure 8 – http://www.lpod.org/coppermine/albums/userpics/Aristarchus%20&%20Herodotus
%20AS15-88-12002.jpg
Figure 9 – http://www.lpod.org/coppermine/displayimage.php?pid=195&fullsize=1
Figure 10 – http://www.damianpeach.com/barbados06/lunar/mons_gruithensen_2006_11_04.jpg
Figure 11 – http://a52.g.akamaitech.net/f/52/827/1d/www.space.com/images/ig298_smart1_moon_06.jpg
Figure 12 – http://www.noaanews.noaa.gov/stories2005/images/solar-flare.jpg
Figure 13 – http://chandra.harvard.edu/photo/2003/gb1508/comptonRadiation.jpg
Figure 14 – http://www.nasa.gov/mission_pages/station/science/experiments/Torso.html
Figure Citations
Figure 15 – http://www.nasa.gov/centers/goddard/images/content/174593main_LRO_Rendering.jpg
Figure 16 – http://www.nasa.gov/centers/marshall/multimedia/photos/2003/photos03-183.html
Figure 17 – http://hyperphysics.phy-astr.gsu.edu/hbase/minerals/imgmin/ilmenitepa.jpeg
Figure 18 – http://en.wikipedia.org/wiki/Image:Rutile-unit-cell-3D-balls.png.
Figure 19 – http://www.nkmz.com/Images/rot5000.jpg
Figures 20-22 – http://aerospacescholars.jsc.nasa.gov/HAS/cirr/em/6/6.cfm
Figure 23 – http://www.timet.com/diagram.html
Figure 24 – ://www.lpi.usra.edu/meetings/resource2000/pdf/7018.pdf
Figure 25 – http://a52.g.akamaitech.net/f/52/827/1d/www.space.com/images/h_lunarbasefs_02.jpg
Figure 26 – Scott Wiedemann
Table 1 – http://lsda.jsc.nasa.gov/books/apollo/Resize-jpg/ts2c3-2.jpg
Table 2 – http://web.princeton.edu/sites/ehs/radsafeguide/rsg_app_e.htm#50
Table 3 – http://www.azom.com/details.asp?ArticleID=1179
Questions?