are cosmic rays?
The base structure of all things is the
atom. Atoms are full of movement, both internally (electrons orbiting the nucleus)
and externally (interacting with other atoms). This movement creates kinetic
energy that is measured in electron volts (eV). The atoms of the air we
breathe move as fast as cannonballs and generate around 0.03 eV. They bounce
into other atoms of air but, like bumper cars at a fairground, they don’t do much
harm to each other.
we find atomic particles moving much faster than this, which create more heat
and more energy. Electrons within the Sun’s plasma have up to 10,000 eV, and
protons in the magnetosphere [*]
are higher still, in the range of 10 - 100 million eV.  The atomic particles in the magnetosphere
move at speeds of 400-800 kilometres per second.
is all rather calm relative to the greater universe. Bombarding the Earth
from light years away are the ions we call cosmic rays.
[†] They can move close to the speed of light and can pack a walloping
50 joules of kinetic energy (3 × 1020 eV). That’s the power of a cricket
ball moving at 160 km/h, packed into the size of a sub-atomic particle.
cosmic rays are the nuclei of atoms (protons), ranging from the lightest to the
heaviest elements in the periodic table. The lightest elements are the most common,
with hydrogen (89%) and helium (10%) dominating, along with other light elements
(lithium, beryllium and boron). A few will be medium elements like carbon or
oxygen, with heavier elements becoming less and less common. This is a similar
relative abundance to the elements within our solar system.
This is just a small portion of my online book, Survive 2012 - a
look into possible ways our world might end, and how to survive. Available
in bookstores sometime before 2012, fingers-crossed...|
In 1912 Austrian-American physicist Victor
Hess found that his electroscope discharged more rapidly as he ascended in a balloon.
He theorised that there must have been radiation entering our atmosphere from
outer space, which he dubbed cosmic rays. In 1936 he was awarded the Nobel Prize
for his discovery.
Where do they come from?
Cosmic rays hit Earth from
every direction, but this tells us nothing of the location of their original source.
Because they are magnetically charged, any interaction with a magnetic field,
even an extremely weak one, will change their path. They are constantly deflected
by magnetic fields throughout the galaxy, until any clues to their origin is lost.
(However, it is possible to trace cosmic rays in other regions of the galaxy by
the electromagnetic radiation they produce).
Within our local planetary system
the solar wind creates a magnetic field of its own. This makes it difficult for
cosmic rays to make it to Earth - there is a correlation between the peak of the
sunspot cycle and fewer cosmic rays reaching Earth.
We don’t know where all the cosmic
rays come from. The Sun emits low energy cosmic rays, typically accompanying
solar flares. But even if every star in the known universe created cosmic rays
in a similar manner, they would only explain a fraction of them.
majority are believed to come from supernova explosions [‡] , which occur approximately
once every 50 years in our Galaxy. They either originate from the explosion itself,
or are created by the shock waves interacting with the surrounding interstellar
gas. This reasoning is based on the energy requirements for creating cosmic rays,
with only supernovas being deemed powerful enough to make them. In both cases
the ejected matter expands at supersonic velocities, accelerating nuclei from
the material they pass through, transforming them into cosmic rays.
Other sources could be neutron
stars, radio galaxies, X-ray binaries (such as Cygnus X-3), active galactic nuclei
(AGNs) and black holes.
To measure cosmic
rays directly, before they have been slowed down and broken up by the atmosphere,
particle detectors can be placed on spacecraft and high altitude balloons.
 Or they can be detected indirectly on our planet’s surface.
When cosmic rays collide with atoms in the upper atmosphere, they create secondary
particles (pions, electrons, positrons) which shower down to the Earth, spreading
out over hundreds of metres. A grid of a hundred or so detectors is used to sample
this area. The more particles that are detected, the stronger the cosmic ray.
The atomic number of the cosmic ray’s nucleus cannot be discovered using this
technique, just statistics of size and frequency. The biggest registered so far,
a 50-joule cosmic ray, was at a Utah
desert observatory in October 1991. On average one of this size will enter
our atmosphere every second.
The world’s biggest
cosmic ray observatory is being
built in Argentina and will be operational in 2004.
rays of this size are labelled "ultra high-energy". To date, scientists
have been unable to determine the limits of the cosmic-ray spectrum, simply because
they lack a detector large enough. The more powerful the particle, the less common
it is, and the larger a detector needs to be to spot it. So even when the galaxy
is quiet, there may be much larger cosmic rays hitting Earth and going undetected.
high-energy cosmic rays are a puzzle for scientists. Astrophysicists have decided
that only black holes of a billion solar masses would have the energy to create
them. Because interaction with the universal microwave background (remnants of
the Big Bang) causes them to lose energy, their source cannot be more than 30
million light-years away. But within our own galaxy there are no known mechanisms
to create such powerful particles. 
An obvious answer comes to mind that most scientists will have
difficulty accepting, that something within our galaxy - that has yet to be
observed - could create them.
It is understandably
hard for us to recreate the conditions of the cosmos here on Earth. The most
modern artificial vacuums do not come close to achieving the emptiness of space,
which has a density as low as one atom per cubic centimetre. Because ultra high-energy
cosmic rays move close to the speed of light, time-scale adds to the problem.
If we could observe a cosmic ray for 10,000 years, from the particle’s point of
view only one second will have passed  . Viewing it for
a microsecond in a particle accelerator will not tell us much. The complicated
electrical and magnetic fields of outer space add to the difficulties. So, even
if we can estimate where cosmic rays come from, we have no idea how they are created.
And the time scales are impossible to recreate. Guesses and theories abound.
Definitive answers do not.
Is the rate of bombardment constant?
This is one reason why carbon dating (http://www.sigmaxi.org/amsci/articles/00articles/taylorcap2.html)
(the carbon isotopes they measure are created by cosmic rays) is inaccurate, because
it assumes that the rate is a constant, which is a typical gradualist way of looking
at things. Evidence from a half-metre long stalagmite that grew between 45 000
and 11 000 years ago in a cave in the Bahamas, shows that the cosmic ray intensity
for that period was double what it is today - see here
for more info.
What happens when they hit earth?
combined energy of all the cosmic rays approaching Earth is massive. Fortunately
the atmosphere and magnetosphere
[§] protect us from them as effectively as a slab of concrete four
metres thick. Even so, when cosmic rays collide with atoms in the upper atmosphere,
they release showers of gamma rays, X-rays and subatomic particles. Most of these
secondary particles will make it to the Earth’s surface. And the most energetic
fragments, although rare, are capable of penetrating miles underground. 
structures mainly consist of space - space between the nucleus and electrons,
space between the individual atoms. Because of this, sub-atomic particles can
travel a great distance before they collide with anything. Consequently most
cosmic rays and secondary particles pass right through houses, trees, rocks, birds
and humans. But a few will occasionally crash into atoms within these structures
and beings. Don’t be too alarmed; this cosmic radiation is minor compared to
the Earth’s natural background radiation, which in total hardly affects any of
us at all anyway.
Thousands of rays and fragments
pass through our bodies every minute.
 Outside of the Earth’s atmosphere, where some satellites and
astronauts roam, cosmic rays are very dangerous indeed - their sheer frequency
means they can ionise electronic circuitry and mutate the genes of astronauts.
How dangerous is flying?
Altitude matters. Whether
you are flying in an airplane or living at a high altitude such as Tibet - the
amount of cosmic radiation your body must deal with is increased.
solar radiation storms, passengers on jets flying nearer Earth's poles can get
with than the equivalent of 10 chest X-rays
in the American Journal of Epidemiology examined the incidence of cancer among
2,740 Air Canada pilots. The group had a sharply higher incidence of four specific
types of cancer compared to the general population: myeloid leukemia, astrocytoma,
prostate cancer, and malignant melanoma.
leukemia is definitely associated with radiation exposure, and occurred
in the Air Canada pilot group four times more frequently than in the general population.
A Danish study
also found an association between exposure to cosmic radiation and leukemia among
aircrew - it was published in Lancet 1999; 354: 2029-31
(a type of brain cancer) occurred twice as often in the Air Canada pilot
group as in the general population, and increased incidence has also been found
in other studies of airline pilots.
higher incidences of prostate cancer were found in both the Air Canada
study and another study of British Airways pilots. Current thinking is that this
might be related to electromagnetic radiation from weather radar and other avionics
rather than from cosmic radiation.
- A study of female
airline flight attendants in Finland and Denmark showed an increased incidence
of breast cancer, and a study of male U.S. Air Force pilots showed they
had significantly more genital and testicular cancer than non-flying USAF officers.
2000, the European Union introduced legislation which requires all European airlines
to monitor cosmic radiation levels during flight and to inform aircrew of the
possible health risks.
"Airline pilots, crew,
and passengers definitely are hit by more cosmic radiation than someone on the
ground. The radiation is stronger at higher altitudes, and especially over the
poles. Individual flights are almost certainly not a problem, since the radiation
will never get anywhere near the 2.5 millirem per hour maximum allowable radiation
dose (OSHA) even for a 41,000 ft flight right over the poles. But it is possible
that pilots and crew accumulate enough to slightly increase their cancer risk.
A Finnish study showed a higher breast cancer rate for stewardesses than for non-stewardesses,
but there are other environmental factors (air quality for instance) that could
The weight of shielding required to
protect against this radiation would make these flights nearly impossible. So
there's not really anything you can do except decide not to fly."
The invisible passenger : radiation risks for people who fly by Robert
Time Magazine - JULY
9, 2001, VOL.158 NO.1
to become a legal issue is the worry over cosmic radiation. According to the Federal
Aviation Administration, at 12,000 m air travelers are exposed to as much as 265
times the radiation dose they receive on the ground. Some airlines take pregnant
female flight attendants off airborne duties to avoid exposing the fetus to cosmic
rays. Passengers who make a transpolar journey, like the new direct Hong Kong-New
York routes operated by Continental Airlines, United Airlines and, from September,
Cathay Pacific, receive on average the equivalent to three chest X rays. (The
rays concentrate around the North Pole's magnetic attraction.) Five round-trips
on these flight paths would put the traveler in excess of the recommended annual
limit for exposure to radiation, experts say. Already, since the flights commenced
in March, Continental and United have rerouted one each, Continental citing passenger
health concerns, United radio interference from solar radiation. (United said
last week it was canceling its flight from next month for business reasons.) Maria
Blettner, head of Germany's Radiation Protection Commission, is finishing a large-scale
mortality study on cancer among flight crews, which is examining the medical history
of 22,000 pilots and 50,000 flight attendants. Results are due soon, but Germany's
Cockpit Association, a professional organization of pilots and engineers, warns
the findings will reveal breast-cancer rates among stewardesses may be twice as
high, and skin-cancer rates up to 15 times as high as those of the general populace."
Although you can’t feel them, cosmic rays, and/or
their secondary particles, pass through you all the time. Mostly they won’t touch
the sides. But, occasionally they will connect with one of your atoms, and, if
your DNA repair system doesn’t kick in, you might in some way mutate. Standard
theories of Darwinian evolution always mention random mutations, but rarely point
out the mechanism behind them - cosmic rays are a leading cause.
current levels, unless you are a pregnant frequent flier, there are many, many
other factors in your daily life that do you more harm. But if the level of cosmic
ray bombardment increases - as it has done in the past - it might be prudent to
investigate ways of shielding yourself from them.
Ray Deflector Society (not serious)
Ray Intensities at Major Cities Worldwide (bottom of the page)
Cosmic Ray Detector
Altitude Radiation Monitoring Service
detector and software
Products and Household Sources Of Radiation
- for measuring an individual’s exposure
exposure for aircrew - a big article from AVWeb
the Moon as a cosmic ray detector
program - allows flight crew to calculate their levels of exposure
2012 at our forumGive the author your thoughts, and discuss any 2012
ideas with others, at 2012 Forum
Comments from Visitors
Interesting. But no reason for desperation, unless we face a supernova.
- Have u study the islamic point of veiw about the end of the world, and are their message identical to the other religions, science and your point of veiw about the end of the world or not?
- I will be waiting for quick responce.
Thank you for providing such an easy to read/understand essay and description of cosmic rays and their impacts on humans and human evolution.
- Considering our species is about to make a major leap toward becoming an "off-planet", space-going species, I can see the subject of cosmic rays will play a major role and be a major consideration in the way we construct our ships.
- Already, those who would see/have us become a space-going species are investigating the impact of space travel on the human body as it relates to survival of the species and procreation. After reading this, I am all the more aware of the difficulties and obstacles our species faces in terms of space travel, accompanying cosmic rays, and their mutative properties. Perhaps Darwin would be pleased were he to know his theories and work is still so helpful in terms of of the human evolutionary process?
a wonderful work,thank u sir
- very interesting n informative...
- really appreciate ur efforts..
- to make science simple
i am waiting for your response [ I can't see anything worth investigating:
- http://www.submission.org/end.html - Rob ]
I wonder how is that energy and speed of cosmic rays measured? Is their energy measured by their speed, or speed measured by energy useing Einsteins equtations? What if they travel faster than light?
Percival Paragados II:
the article is intensely informative, it interests me to know how this cosmic arrays or these secondary particles affect the atmosphere with the presence of many elements and pollutants. i am interested in knowing the chemical reaction and branching processes everytime the cosmic rays enter the atmosphere. perhaps you could enlighten my mind..THANKS! il wait for your kindmost response.
Percival Paragados II:
i mean cosmic rays, not "cosmic arrays" keyboard error.
QUOTE "But, occasionally they will connect with one of your atoms, and, if your DNA repair system doesn’t kick in, you might in some way mutate. Standard theories of Darwinian evolution always mention random mutations, but rarely point out the mechanism behind them - cosmic rays are a leading cause." END QUOTE.
- Yes, cosmic radiation can cause cancer, assuming high exposure. BUT cancer begins with one "mutated" cell, and the change MUST be in the DNA of the cell for it to have any cancerous effects. A tumor cannot grow if the broken cell does not create more copies of itself.
- Your connection to Darwin and evolution, however, is entirely false.
- Firstly, in order for a mutation to have any evolutionary effect at all, that mutation must occur in a reproductive cell (sperm or egg), and that cell must be used in reproduction to create a new being. Otherwise, the mutation simply dies with its body.
- [cont'd next comment]
Secondly, random mutations are NOT a primary source of evolution. While they are necessary for entirely new species to form, mutational evolution is a very very VERY slow process. The primary sources of evolution are migration (as organisms move into/out of populations they bring with them alternative alleles of genes, and if these are more favorable they will be selected for), Genetic Drift (chance: if there is a tornado that wipes out part of a population, the genetic makeup of the survivors could be greatly different from the original population), and Natural Selection (defined as nonrandom differential reproduction of individuals, for example if the girls all want blue-eyed boys, then the boys with eyes of other colors won't get to reproduce and pass on their genes, and soon all boys will be blue-eyed).
- [cont'd next comment]
Thirdly, mutations occur primarily as a result of error in mitosis and (perhaps more so) in meiosis, that is, a mistake when copying the DNA in preparation for making a new cell. If the error occurs in the right stage or location, multiple copies of the error could be present in hundreds or even thousands of reproductive cells, making the likelihood of passing on the mutation high. And, I repeat, mutations not located in reproductive cells are not passed on. Mutations caused by radiation that result in evolution are rare because, as i said before, they must occur in a reproductive cell that gets USED. For the average person, this is two to three cells of their entire body - out of the approximately 100 trillion total cells they have. That's a statistically negligible percentage.
- Fourthly, the majority of mutations result in the death of the cell (or possibly the organism) in question, and that is the end of them. In other words, the majority of mutations are not beneficial, and therefore selected against in evolutionary terms.
- [cont'd next comment]
Fifthly, POPULATIONS EVOLVE, NOT ORGANISMS. I will repeat myself one last time - the mutation must occur in reproductive cells which are USED, and BECOME NEW ORGANISMS in order for it to have a chance at affecting evolution. The mutation must also be beneficial (or at least neutral) for the offspring bearing it to survive and pass it on. And the offspring must then reproduce itself, and pass on the mutation to its own offspring. It takes hundreds or even thousands of millenia for a single mutation to show evolutionary effects.
- I hope you will correct your work to represent these facts accurately, and proceed in the future to more thoroughly research all aspects of your topic.
I would like to contribute the fact that thru the process called spallation, cosmic rays produce many cosmogenic elements such as lithium. Since lithium comes exclusivly from cosmic rays and it is an important part of a healthy nervous system, a certain amount of cosmic energy is needed for optimal health.
- That expalins the increased conflict during solar maxs, when cosmic rays are reduced due to increased energy output from the sun.
- I feel that there is a 2012/lithium connection, but I don't have it all figured out yet.
You hear many references to 2012 and DNA changes. This is where lithium plays its part. Cosmic Rays contain a very high % lithium compared to the universe in general. Being bombarded with increased GCRs will bring us more lithium (and the rest of the LiBeB group)as well as more mutations
I have a question. Is it possible for Cosmic Rays to have an effect on chemical elements while in space? For example, let's say for some reason an astronaut is attempted to bond hydrogen and oxygen to create water. Is it logical to say that Cosmic Rays could somehow alter the chemical properties of these elements to create hydrogen peroxide instead of water?
QUOTE "Electrons within the Sun’s plasma have up to 10,000 eV, and protons in the magnetosphere [*] are higher still, in the range of 10 - 100 million eV." END QUOTE. I just wanted to say that most galactic cosmic rays have energies between 100 MeV (corresponding to a velocity for protons of 43% of the speed of light) and 10 GeV AT POINT OF ENTRY INTO THE EARTH'S ATMOSPHERE. This may be more relevant to the point of this page (which [i'm assuming] has to do with electrons and THE EARTH), rather than informing readers about electrons in the sun's plasma.
The comments section is now closed, but you can still email me, or even
better, visit 2012 Forum
Script by Alex
[*] Magnetosphere: area surrounding the
Earth that is influenced by its magnetic field. Towards the sun it extends for
60,000 kilometres, and away from the sun it forms a tail, created by the solar
wind, with a length of one million kilometres
[†] The term “cosmic ray” is misleading.
Rather than being an actual ray (a thin beam of radiant energy or particles),
it is just a singular particle - anatom that was stripped of its electrons when
accelerated to enormous speeds.
The cosmic rays referred
to here are more properly known as Galactic Cosmic Rays. The general term can
also includes subatomic particles like electrons and positrons, particles arriving
from the sun and particles accelerated in interplanetary space.
[‡] A supernova is a star which has run out of the
"nuclear fuel" of light elements (especially hydrogen), needed to keep
it shining. Its "nuclear burning" gradually converts light elements
into heavier ones, and the heat it produces keeps the star puffed up, resisting
the pull of gravity which would like to draw it together. When the star can no
longer produce nuclear heat, it suddenly collapses to a small volume, releasing
in the process an enormous amount of gravitational energy. Much of that energy
is spent in a grand explosion, blowing the star's outer layers out to space and
creating a huge expanding shock front. (from a NASA website)
[§] The active sun with its large solar wind creates
a large distortion of the magnetic field about the earth (the magnetosphere),
which increases the earth's shielding against intragalactic cosmic rays. This
leads to a net reduction of the sea-level cosmic rays during the period
of the active sun. In the active sun of 1989-1991, which was the most intense
solar activity ever recorded, the sea-level intensity of cosmic rays actually
decreased by about 30%. Thus, the active sun greatly intensifies the solar
wind, and the external particle flux increases, but the earth's distant magnetic
field also increases. The final result of this complex interaction is that the
terrestrial sea-level flux of cosmic particles decreases during the active
sun, except for the few hours during the most spectacular solar flares (from
 Macmillan Encyclopedia of Physics in 1996.
 Macmillan Encyclopedia of Physics in 1996.
 "Cosmic Rays at the Energy Frontier,"
Microsoft® Encarta® Encyclopedia 2000. © 1993-1999 Microsoft Corporation.
All rights reserved. By James W. Cronin, Thomas K. Gaisser and Simon P. Swordy
About The Authors: Cronin, a professor of physics at the University of
Chicago since 1971, shared the Nobel Prize with Val L. Fitch for work on symmetry
violations in the decay of mesons. Gaisser, a professor of physics at the University
of Delaware. Swordy, an associate professor at Chicago, has been active in cosmic-ray
measurement since 1976. He earned his Ph.D. from the University of Bristol in
1979. This article updates a version that appeared in Scientific American
in January 1997.
 Macmillan Encyclopedia of Physics in 1996.
 "Cosmic Rays at the Energy Frontier,"
Microsoft® Encarta® Encyclopedia 2000. © 1993-1999
 Einstein’s Theory of Relativity
 Macmillan Encyclopedia of Physics in 1996.