Cosmic Ray History
Dan Claes
U Nebraska, Lincoln
CROP
http://cse.unl.edu/~gsnow/crop/crop.html
Selected, and a few comments added
by Jim Linnemann
MSU
“If we knew what we were doing, it wouldn’t be
called research, would it?” - Albert Einstein
Special issue
Magnificent
Cosmos
March 1998
Cosmic Rays at the Energy Frontier
James W. Cronin, Thomas K. Gaisser
and Simon P. Swordy
The Cosmic Ray Observatory Project
High Energy Physics Group
The University of Nebraska-Lincoln
Bibliography
Clay, Robert and Bruce Dawson, Cosmic Bullets
(Addison-Wesley, Reading, Massachusetts, 1997)
Friedlander, Michael W., Cosmic Rays
(Harvard University Press, Cambridge, 1989)
or its update,
Friedlander, Michael W., A Thin Cosmic Rain
(Harvard University Press, Cambridge, 2000)
Hayakawa, Satio, Cosmic Ray Physics
(Wiley-Interscience, New York, 1969)
Rutherford, James, Gerald Holton & Fletcher Watson,
The Project Physics Course (Holt, Rinehart and
Winston, Inc., New York, 1970)
with additional images from NASA’s archive at
http://antwrp.gsfc.nasa.gov/astropix.html
+
An electron and a proton are set free, near
each other, deep in outer space. The
electron moves towards the proton with
A) constant velocity ( v = constant )
B) increasing velocity but constant
acceleration ( a = constant )
C) increasing velocity and increasing
acceleration
+
An electron and a proton are set free, near
each other, deep in outer space. The
electron moves towards the proton with
A) constant velocity ( v = constant )
B) increasing velocity but constant
acceleration ( a = constant )
C) increasing velocity and increasing
acceleration
There is a net force on the electron due to the proton’s
charge, so the electron accelerates (A is out). As the
electron moves closer to the proton, the force it
experiences grows stronger (Coulomb’s Law holds F 
1/d2). If the force becomes stronger, and the mass does
not change, then Newton’s Second Law (F = ma or a =
F/m) says that the acceleration increases. The answer to
the question must be (C).
When two identical socks are removed
from a clothes dryer, they will usually
A) repel each other
B) cling to each other
C) no way to predictl
When two identical socks are removed
from a clothes dryer, they will usually
A) repel each other
B) cling to each other
C) no way to predictl
If the socks have acquired a static charge, they will most likely have acquired charge
of the same sign, and repel each other. What determines if a material picks up
electrons is the property called electron affinity. The socks acquire their charge by
coming into contact will all the other clothes in the dryer. If the socks come in
contact with material of a higher electron affinity, the socks will give up electrons to
that material. When they come into contact with materials with a lower electron
affinity, they will acquire electrons. Both socks will thus acquire the same charge,
for the most part.
Of course, it is possible that in the random mixing of clothes in the dryer, one of
the socks only comes into contact with materials which take electrons from it, and
the other socks rubs against materials which give up electrons. The socks will then
have opposite charges and attract. However, this is more unlikely.
The answer is (A).
Moving charge by friction
Some atoms/molecules
attract electrons more
strongly than others.
Affinity: a natural liking
or sympathy
Electron Affinity
rabbit’s fur
glass
wool
silk
rubber
hard plastic
close:
far:
stronger weaker F  1
d2
attraction attraction
electron
jumps
Different materials have
different electrons affinities
plastic rod
fur
When fur is rubbed on a plastic rod,
both acquire an equal but opposite charge.
If the fur merely rests on top of the plastic,
each will acquire equal and opposite charges.
T) True.
F) False. Friction is necessary to provide
enough heat (energy) for electrons
to jump from the fur to the plastic.
plastic rod
fur
When fur is rubbed on a plastic rod,
both acquire an equal but opposite charge.
If the fur merely rests on top of the plastic,
each will acquire equal and opposite charges.
T) True.
F) False. Friction is necessary to provide
enough heat (energy) for electrons
to jump from the fur to the plastic.
The answer is True. It is not necessary to rub the fur on the rod. If they simply
come into contact with no motion between them, electrons will still jump from the
plastic to the fur. Why, then, is the fur rubbed? Because the contact between the
plastic and the fur is a bunch of random, jagged edges. (Remember friction!)
plastic
fur
In the figure above, there are only about three contact points where the atoms are
close enough for the electrons to make the jump. If instead the fur and plastic are
rubbed, many, many more atoms come into contact with each other and more
electrons can make the big move. The plastic and fur thus acquire more charge,
which makes it more noticeable.
Far apart:
electrons stay with
their own atoms
 both atoms neutral
electron
Close:
difference in electron
affinity. Electron jumps.
Move apart: electron stays with the
atom it jumped to
 both atoms charged
Note: only contact between atoms is necessary.
The heat of friction plays no role.
1900 While studying atmospheric electricity,
J. Estler and H. Geitel note an unknown, but
continuously present source of ions “in the air”
Charles T. R. Wilson’s ionization chamber
Electroscopes eventually discharge even
when all known causes are removed,
i.e., even when electroscopes are
•sealed airtight
•flushed with dry, dust-free
filtered air
•far removed from any
radioactive samples
•shielded with 2 inches of lead
seemed to indicate an unknown radiation with greater
penetrability than x-rays or radioactive  rays
Speculating they might be extraterrestrial, Wilson ran
underground tests at night in the Scottish railway, but
observed no change in the discharging rate.
1909 Jesuit priest, Father Thomas Wulf , improved the
ionization chamber with a design planned
specifically for high altitude balloon flights.
A taut wire pair replaced the gold leaf.
This basic design became the pocket
dosimeter carried to record one’s
total exposure to ionizing radiation.
1909
Taking his ionization chamber
first to the top of the Eiffel Tower
(275 m)
Wulf observed a 64% drop in the discharge rate.
Familiar with the penetrability of radioactive    rays,
Wulf expected any ionizing effects due to natural radiation
from the ground, would have been heavily absorbed by the
“shielding” layers of air.
Henri Becquerel (1852-1908)
received the 1903 Nobel Prize
in Physics for the discovery
of natural radioactivity.
Wrapped photographic plate
showed clear silhouettes, when
developed, of the uranium salt
samples stored atop it.
1896 While studying the photographic images of various
fluorescent and phosphorescent materials, Becquerel
finds potassium-uranyl sulfate spontaneously emits
radiation capable of penetrating
•thick opaque black paper
•aluminum plates
•copper plates
Exhibited by all known compounds of uranium
(phosphorescent or not) and metallic uranium itself.
1898 Marie Curie discovers
thorium (90Th)
Together Pierre and
Marie Curie discover
polonium (84Po) and
radium (88Ra)
1899 Ernest Rutherford identifies 2 distinct kinds of rays
emitted by uranium:
 - highly ionizing, but completely
absorbed by 0.006 cm aluminum
foil or a few cm of air
 - less ionizing, but penetrate many
meters of air or up to a cm of
aluminum.
1900 P. Villard finds in addition to  rays, radium emits
 - the least ionizing, but capable of penetrating
many cm of lead, several feet of concrete
+
Magnitude of
Magnetic Force
Lorentz Law
Magnetic force is related to q, v and B
Experimental observations:
• force depends on the direction of v relative to B
• if v is parallel to B  F = 0
• if v is perpendicular to B  F = Fmax
• if v is at angle q from B  F = Fmax sinq
F = q v B sinq
Direction of
Magnetic Force
Drawing vectors in
tail
head
out of
in to
page
page
Direction of magnetic
force is “sideways”
•force is perpendicular
to both v and B
•use “right-hand” or
“left-hand rule” to
find its direction
F = q v B sinq
An uncharged particle enters a
region with the magnetic field
shown. What path will it follow?
B field
x x x x x x x x x x x x
A
x x x x x x x x x x x x
x x x x x x x x x x x x
x x x x x x x x x x x x
x x x x x x x x x x x x
x x x x x x x x x x x x
D
C
B
A charged particle moves
in a straight line through
some region of space.
The net magnetic field
in this region must be zero.
T)True
F) False
X
B field
Y
Z
Imagine three particles A, B and C all with the
same mass, but different charges. (Particle
B is neutral). When A enters the magnetic field,
it follows path Z.
When particle B enters the magnetic field, it will
follow path
A) X
B) Y
C) Z
When particle C enters the magnetic field, it will
follow path
A) X
B) Y
C) Z
B-field
points
into page
From these observations alone,
what definite conclusions can be made?
A. s are positively charged, s negative.
B. s are negatively charged, s positive.
C. can only say , oppositely charged.
X
B field
Y
Z
Imagine three particles A, B and C all with the same mass,
but different charges. (Particle B is neutral). When A
enters the magnetic field, it follows path Z.
When particle B enters the magnetic field, it will follow path
A) X
B) Y
C) Z
When particle C enters the magnetic field, it will follow path
A) X
B) Y
C) Z
The answer to the first question is (2). A magnetic field exerts forces on moving
charges. If there is no charge (as for a neutral particle) there is no force. The Lorentz
Force Law says that F=qvB when v and B are perpendicular. If q=0, the F=0.
The answer to the second question is (3). The charge of C is opposite that of A, which
we can write as q(C) = q(A), so F(C) = F(A). A minus sign on a vector means that
it points in the opposite direction. So if A follows path X, then C must follow path Z.
1900-01 Studying the deflection of these rays in
magnetic fields, Becquerel and the Curies
establish   rays to be charged particles
Using the procedure developed by J.J. Thomson in 1887
Becquerel determined the ratio of charge q to mass m for
: q/m = 1.76×1011 coulombs/kilogram
identical to the electron!
: q/m = 4.8×107 coulombs/kilogram
4000 times smaller!
1900-01
Noting helium gas often found trapped in samples of
radioactive minerals, Rutherford speculated that 
particles might be doubly ionized Helium atoms (He++)
1906-1909 Rutherford and T.D.Royds develop their
“alpha mousetrap” to collect alpha particles
and show this yields a gas with the
spectral emission lines of helium!
1896
1899
1912
 

s are ionized Helium (bare Helium nuclei)
2-protons, 2-neutrons (positively charged)
s are simply electrons(negatively charged)
q = 2q
m=7296m
1911-12
Austrian physicist Victor Hess, of the Vienna University,
and 2 assistants, carried Wulf ionization chambers up in
a series of hydrogen balloon flights.
• taking ~hour long readings at several altitudes
• both ascending and descending
• radiation more intense above 150 meters than at sea level
• intensity doubled between 1000 m to 4000 m
• increased continuously through 5000 meters
Dubbed this “high” level
radiation
Höhenstrahlung
Hess lands following a
historic 5,300 meter flight.
August 7, 1912
National Geographic photograph
In 1936, Hess was awarded the Nobel prize for this discovery.
Cosmic ray
strikes a nucleus
within a layer of
photographic
emulsion
50mm
1913-14 Werner Kolhörster of Berlin’s
Physikalisch-Technische Reichsanstalt
•ascends to 9300 m (height of Mount Everest,
cruising altitude of a passenger jet!)
•ionization rate 50× that at sea level!
1925-26 Robert Millikan of Caltech (winner of the 1923
Nobel prize) initially fails to duplicate such results
• over San Antonio, Texas, found “not more than
25% of that found by European observers.”
Further high-altitude measurements made in
collaboration with Ira S. Bowen confirmed the
existence of what Millikan coined “cosmic rays”.
Ionization chambers grow
more robust and reliable.
Automated to work and be
recorded remotely.
1911 Rutherford’s assistant Hans Geiger develops a device
registering the passage of ionizing particles.
1924 Walter Bothe and Geiger use multiple Geiger counters
to establish the tracks followed by electron beams
1928-29 Bothe and Werner Kolhörster build Geiger telescopes
and announce cosmic “rays” contain charged particles
1927-28 Jacob Clay
from Genoa to the Dutch colony of Java
•ionization intensity drops ~6%
•minimum at magnetic equator
1929 Bothe & Kolhörster
•suggest Clay’s Lattitude Effect was due to
•deflection by earth’s magnetic field
•primaries are charged
• inspired by the Norwegian mathematician Carl Størmer’s
calculations explaining colleague Kristian Birkland’s theory
of the aurora
• Birkland experimented with electron beams
and a phosphorous-painted globe of lodestone
Earth’s magnetic field is approximately that of a bar magnet.
• Field strength is not the same everywhere
stronger at the poles
• Field angle is different in different locations
vertical at poles, horizontal at magnetic equator
• South magnetic pole is at north geographic pole
Magnetic axis does not line up with rotation axis
• compass correction depends on location
New York 10° W
Chicago
0°
L.A.
18° E
Magnetic poles move, and sometimes
reverse direction
Location of S magnetic
pole over last century
Cause: Not fully understood, but is somehow due to motion
of charged particles in Earth’s molten interior.
But why aren’t poles aligned with rotation axis?
Other astronomical bodies with magnetic fields:
Mercury and Jupiter, The Sun, The Milky Way galaxy
The North pole of a small
magnet (compass) points
towards geographic North
because Earth’s magnetic
South pole is up there!!
The field lines of the
Earth’s field are
not parallel (except
at the equator) to the
surface of the earth “Dip Angle”
1995•
80o
1975•
1948•
1904•
70o
Northwest Territories
The magnetic pole is not exactly
at geographic north (compass
corrections needed). The poles
in fact drift, and occasionally
reverse polarity!
1930-33 Arthur Compton (University of Chicago) conducts
a worldwide sea- and mountain-level lattitude survey of
cosmic ray intensities and confirms the Latitude Effect.
The 4 curves correspond to 4 seasons.
Physical Review 52 [1937]:p.808
Størmer’s “cutoff energies”:
only the fastest cosmics reach sea level near the equator
 less energetic particles are observable at mid-latitudes
 unrestricted energies in the polar regions

September 21, 1932 Millikan completed a series of
tests on the intensity of cosmic rays at various altitudes in a
Condor bomber from March Field, California.
1933-35 Thomas Johnson (of the Carnegie Institute) and
Bruno Rossi (Italy) independently mount
Geiger counter telescope arrays to test for the
east-west asymmetry
predicted by Georges Lemaître (Belgian)
Positive charged particles headed toward the earth
from space, would tend (at mid-latitudes) to reach
the surface coming down from the
A. North
B. South
C. East
D. West
E. split East and West
Although cosmic rays do come
“from all directions”,
at high altitudes near the equator
the intensity is higher coming from
the West than from the East!
1939 Johnson speculates primaries may be protons!
Electroscopes become so robust, data
can be collected remotely (for example
retreived from unmanned weather balloons)
November 11, 1935
Explorer II,
a 113,000 cubic foot
helium balloon
ascends to a record
22,066 m
while collecting
atmospheric and
cosmic ray data.
1937-1939 Studies of Extended Air Showers begin
in France when by accident Pierre Auger and his
Russian colleague Dimitry Skobeltzyn notice
apparent coincidence between Cosmic Ray
telescopes set up several hundred meters apart.
Cloud chamber photographs
by George Rochester and
J.G. Wilson of Manchester
University showed the large
number of particles contained
within such showers.
1936 Millikan’s group show that at the earth’s surface
showers are dominated by electrons, gammas, and
X-particles
capable of penetrating deep underground
(to lake bottom and deep tunnel experiments)
characterized there by
isolated single cloud chamber tracks
Definite evidence for the celestial generation of Cosmic
Rays came from fortuitous timing of a few high altitude
balloon studies during some spectacular solar flares.
Unusual increase in Cosmic ray intensity associated with
an intense solar flare observed
February 28, 1942
the same sunspot associated with this flare erupts again
March 7, 1942
Similarly the
June 4, 1946 solar prominence
is followed by another eruption
July 25, 1946
and the solar flare event of
November 19, 1949
is also captured by airborne cosmic ray instruments
each accompanied by a Sudden Ionospheric Disturbance
which interrupts radio communications on earth
During the June 1946 prominence,
ultraviolet radiation and x-rays arrived
A. shortly before
B. simultaneous to
C. shortly after
the visual observation of the flare.
Why?
During the June 1946 prominence,
charged particles causing
radio blackouts arrived
A. hours before
B. minutes before
C. simultaneous to
D. minutes after
E. hours later
the visual observation of the flare.
Particles causing radio
blackouts arrived about 3
hours later.
Why?
During the June 1946 prominence, ultraviolet radiation and
x-rays arrived simultaneous to the visual observation of the
flare. Why? Radio interference began immediately. Charged
particles causing radio blackouts arrived about 3 hours later.
But ground-based monitoring stations at low magnetic latitudes
observed no increase. Why?
However on
November 14, 1960 Explorer VII detects solar flares causing
“extremely severe” magnetic disturbances in the Earth's
atmosphere. The sea level neutron counter at Deep River,
Canada records:
J.F.Steljes, H.Carmichael,
K.McCracken, Journal of
Geophysical Research 66
[1961]:p.1363
and the National Bureau of Standards measures
extensive attenuation of radio transmissions
May 11, 1950
A Naval Research Viking research rocket fired from the
U.S.S. Norton Sound near Jarvis Island in the Pacific
collects cosmic ray and pressure and temperature data.
1952-57 James A. Van Allen (University of Iowa)
reports the 1st high altitude survey
of total cosmic-ray intensity and
latitude variation of heavy nuclei
in primary cosmic radiation, from
his “Rockoon” (balloon-launched
rocket).
February - March, 1958
U.S. Satellites Explorer I and II carry Geiger-Müller
counters for Van Allen looping through highly eccentric
(50 km perigee, 2600 km apogee) orbits every 2½ hours.
 Cosmic
ray intensities increase steadily with altitude
until 2000 km when counters suddenly registered nothing.
 Lab tests of duplicate counters suggested they had been
overloaded by a region with a sudden 15000× increase
in cosmic rays!
1958 Explorer IV and Sputnik III confirm, what is
eventually mapped as 2 gigantic radiation belts
of trapped ions.
October 13, 1959
Explorer VII was launched. into an Earth orbit. By late
December its data reveals
•inner belt mostly protons
•outer belt mostly electrons
July 31, 1961
NASA funds high-altitude balloon measurements of the
proton and alpha-particle spectrum of primary cosmic
radiation conducted by the University of Chicago above
Uranium City, Saskatchewan, Canada.
August 17, 1961
Explorer XII radios data on magnetic fields and cosmic
rays from a 54,000 mile apogee (and 170 mile perigee).
1962
Enroute to Venus Mariner II detects a continuously
flowing solar wind of fast and slow streams, cycling
in 27 day intervals (the rotational period of the Sun).
July 1969
Apollo 11 astronauts trap cosmic ray particles on
exposed aluminum foil, returned to earth for analysis
of its elemental and isotopic composition. With no
atmosphere or magnetic field of its own, the moon’s
surface provides a constant bombardment of particles.
July 1969 Apollo 11 astronauts trap cosmic ray particles on
exposed aluminum foil, returned
to earth for analysis of its
elemental & isotopic composition.
With no atmosphere or magnetic
field of its own, the moon’s surface
is exposed to a constant barrage of
particles.
March 3, 1972
Pioneer 10 launched -on its flyby mission, studies
Jupiter's magnetic field and radiation belts.
December 1972
Apollo 17’s lunar surface cosmic ray
experiment measured the flux of low
energy particles in space (foil detectors
brought back to Earth for analysis.
October 26, 1973
IMP-8 launched. Continues today measuring cosmic rays,
Earth’s magnetic field, and the near-Earth solar wind from
a near-circular, 12-day orbit (half the distance to the moon).
October 1975 to the present
GOES (Geostationary Orbiting Environmental Satellite)
An early warning system which monitors the Sun's surface
for flares.
1977 The Voyager 1 and 2 spacecraft are launched. Each
will explore acceleration processes of charged particles
to cosmic ray energies.
August 31, 1991
Yohkoh spacecraft launched - Japan/USA/England solar
probe - studied high-energy radiation from solar flares.
July 1992
SAMPEX (Solar Anomalous and
Magnetospheric Particle Explorer)
in polar orbit. By sampling interplanetary & magnetospheric particles,
contributes to our understanding of
nucleosynthesis and the acceleration
of charged particles.
July 1992
IMAX (Isotope Matter-Antimatter eXperiment) balloonborne superconducting magnetic spectrometer measured
the galactic cosmic ray abundances of protons, anti-protons,
hydrogen, and helium isotopes.
August 25, 1997
Advanced Composition Explorer (ACE)
was launched!
A few more practical
Cosmic Ray effects
• Produces Carbon 14 from Nitrogen 14
– nuclear transmutation
– basis of radiocarbon dating
– depends on near-constant flux of cosmic
rays
• Cause computer memory errors!
• Natural source of genetic mutations
– Worse in Denver
– And for those on airplanes a lot
• Everyday demonstration of special
relativity
Change a proton to a neutron and
Nitrogen 14 becomes Carbon 14
http://pearl1.lanl.gov/periodic/default.htm
brief communications
Space travel
Dual origins of light
flashes seen in space
L
ight flashes are unusual visual phenomena that
are observed in space and are caused by the
interaction of energetic cosmic-ray particles with
the human visual system. Using data gathered on
board the Mir space station during the Sileye-2
experiment1 , we show here that there are two
separate components of cosmic rays that cause
these flashes: one due to heavy nuclei and one due
to protons. This indicates that perception by an
astronaut’s visual apparatus could involve two
complementary mechanisms.
Ever since light flashes in space were predicted2
before the first space mission and subsequently
reported by early Apollo astronauts, attempts to
determine their cause have been made both in space
and using ground-based particle accelerators3. As a
result, several explanations have been proposed to
account for the phenomenon ( see ref. 4 and
references therein ).
The measured rate of occurrence of light flashes
(LF) varies for different missions: on Mir5, it
is much lower ( Sileye-1, 0.18  0.02 LF min-1;
Sileye-2, 0.130.01 LF min-1) than on Apollo6
( 0.23  0.1 LF min-1), Skylab7 ( 1.3  0.1 LF
min-1) and ASTP8 (0.460.05 LF min-1). This effect
is probably due chiefly to a reduction in the speed
of low-energy particles by Mir’s hull material
(aluminium more than 3 mm thick) and the equipment inside the craft.
As light flashes are caused by particles interacting with the human visual apparatus, their occurrence should be proportional to particle rate (the
so-called ‘latitude effect’). Particle rates outside the
region of the South Atlantic Anomaly ( SAA )
depend on the geomagnetic cut-off, which is a
function of the position-dependent geomagnetic
field intensity and direction. The cut-off C
represents the minimum rigidity for cosmic rays to
reach Mir’s orbit without being deflected outwards;
680
© 2003 Nature Publishing Group
Figure 1 Rate of occurrence of light flashes on board the Mir space
station as a function of particle rate for all particles and for relativistic
nuclei inside(circles) and outside(squares) the South Atlantic Anomaly.
a, Plot of light-flash rate against proton rate; b, light-flash rate against
particle rate for particles with linear-energy transfer of §20 keV mm-1.
Linear fits for each region are shown. Data are from the Sileye-2
experiment1, where astronauts wore light-excluding helmets integrated
with cosmic-ray particle-flux detectors, enabling the frequency of
flashes to be recorded as a function of background flux & orbit position.
it is lower at high geomagnetic latitudes ( for Mir’s
orbit, the lowest cut-off is C = 0.6 gigavolts (GV))
and higher at the geomagnetic equator ( where
maximum cut-off is C = 16 GV). The lower the
cut-off, the higher the rate of particles coming from
outside the Earth’s magnetosphere ( we use the
vertical cut-off at each location of Mir).
Light-flash and particle rates measured inside
Mir were divided in 3-GV bins that separated the
regions outside ( C ≤ 18 GV ) and inside the SAA
(3 ≤ C ≤15 GV, selected for Earth’s magnetic field
B  2.510-5 tesla; Fig. 1). The light-flash rate, RLF,
is plotted against the particle rate, P, for all particles
(almost exclusively protons) in Fig.1a. In Fig.1b,
RLF is plotted as a function of the rate of relativistic
nuclei, Pn, with charge Z ≥ 6, obtained by selecting
particles with high linear-energy transfer ( 20 keV
mm-1) to guarantee the complete removal of the
proton component.
From the all-particle plot (Fig. 1a), it is possible
to see that RLF is not linearly proportional to proton
flux in all regions: in the SAA, it is roughly
independent of proton rate ( even though statistical
errors preclude any further claim ). For instance, at
the centre of the SAA (9≤C≤12 GV), where particle
NATURE | VOL 422 | 17 APRIL 2003 | www.nature.com
A new view of the
atmosphere?
• Cosmic ray target
• Cosmic ray shield
Cosmic Rays Have Had
A Typical Scientific
Cyclic History
“Interesting” is a relative term:
• First an annoying ill-understood effect that
muddies measurements
– A “background”
• Study and understand the phenomenon
– Now a signal
• Use as a tool to probe the unknown
– High energy physics discoveries ’30’s – 50’s
• Highest energy accelerator available!
– Currently: exploring the universe
• Well-understood parts become an annoying
background to the interesting parts
THE COSMIC RAY
DEFLECTION SOCIETY
OF
NORTH AMERICA
http://www.geocities.com/SunsetStrip/1483/