CHAPTER 1 -- WHY STUDY SPACE?
© John F. Graham, 1995
In the middle of the Twentieth Century an event on the third small rocky
planet from the center of an average star occurred the like of which had not
happened since the first animal crawled out of the planet's watery seas and
evolved to live on land. A species departed from its home environment into
another so austere and so hostile that without a small replica of the planet in
which to survive the representative of that species may have easily perished.
The planet from which the species departed was the Earth; the species which
departed the Earth was called humanity; and the place to which it departed was
called space.
By selecting this book about space studies you have chosen to embark upon a
remarkable journey. It's a journey, which tells of heroes and heroines,
explorers, businessmen and women, entrepreneurs, scientists, engineers, doctors,
lawyers, politicians, diplomats, and blue-collared workers. It is a story of the
ongoing efforts of humanity to depart the cradle of its birth and journey into a
wondrous and forbidding place - outer space.
This book will not attempt to relate every detail of the human effort to
explore space; to do so would require an immense library. What it will do is to
browse through that library, selecting interesting highlights which will not
only introduce the reader to the space program, but will also provide
information of such interest that it should be easily retained. This book will
not serve as a career guide, but it may entice the interested reader to delve
into certain aspects of the space program more thoroughly and hopefully inspire
everyone to become more involved in humanity's next great adventure.
Why Study Space? The greatest purpose is interest. There are a number of
reasons to become interested in outer space. Perhaps the adventure and romance
of exploration are enough to pique one's interest. Maybe the individual read a
science fiction book about space such as Arthur C. Clarke's 2001 or Rendezvous
With Rama. Possibly a person may have seen one of the many popular space movies
such as Star Wars, The Empire Strikes Back, The Return of the Jedi, Battle Star
Gallactica, or Buck Rogers. More than likely, an individual may have seen a
television show such as The Challenger or older fare such as Flash Gordon or Tom
Corbett: Space Cadet. Perhaps the interest may have been developed from watching
actual launches of the space shuttle or viewing movies of the Apollo Moon
Landings. Whatever the method from which the reader's interest came, the idea of
humans departing the planet into space is fascinating.
Other than interest, science and technology have made great strides during
the years since the advent of the space program. Rocket vehicles have been
developed which can withstand great amounts of stress and temperature variances.
The science of orbital mechanics, for years on the ground because no method of
getting into space had been developed, was not only proven true but also
advanced as humanity went to the Moon and other bodies in our Solar System.
Planetary Geology was strictly Earthbound until the Apollo Program and a number
of space probes which went to the planets literally rewrote the entire science.
Astronomy books are being rewritten daily as discoveries pour in from the Hubble
Space Telescope, the International Ultraviolet Explorer, and the Voyager space
probes.
Computer Science was zoomed into the future by the space program. President Kennedy was often said to be the true founder
of IBM when he challenged the United States within a decade to send a man to the
Moon and return him safely to Earth. This dictated the need to develop smaller
and faster computers and led directly to integrated circuits, the microprocessor
and our modern computers.
Medicine profited directly from the space program as the remote sensing of an
astronaut's bodily functions led to heart pacemakers, CAT scans and remote
sensing monitoring of critical patients in today's Intensive Care Units. The
intricate functions of the human body are studied daily by astronaut/cosmonaut
doctors as humans are establishing a beachhead in the low Earth orbits aboard
space stations. A serious problem facing the astronauts such as calcium loss in
the bones has helped to study an Earthbound skeletal disease, osteoporosis.
Electrophoresis experiments in space have led to a number of new drugs used for
Earth diseases such as diabetes and AIDS. Perhaps a cure for cancer may someday
come from experiments run in space.
Earth sensing, the monitoring of our Earth from space, obviously came from
the space program. What are factories and rain forest burnings doing to our
planet? Is the ozone hole a real phenomenon or just scientists' conspiring to
bilk millions of dollars from the government for their own pet experiments? Can
remote sensing of the Earth be used to find out what's wrong with the planet and
if so, how do we fix it? The answer could lie in how we use the space program.
There are a myriad of other arguments for exploring space such as increasing
knowledge, using applications, developing technology, and advancing economic
growth. Because they will inherit the future our young people must be inspired
to aspire to greater accomplishments in education. Providing such inspiration is
a very important intangible benefit of space exploration.
The space exploration missions have produced basic knowledge about our
planet, our environment, the solar system, and the universe which would have
been nonexistent if we did not have a space program. This information has given
us a deeper awareness of the history of our Earth and how we can make better
decisions concerning life on our planet and improve it for ourselves and our
posterity.
Applications from the space program have made life a totally different
experience than it was forty years ago. Who would have dreamed at that time of
picking up a telephone and within thirty seconds speaking to a friend in
Australia and hearing them as if they were in the next room? Nightly, we receive
live television news reports from such places as Somalia, Beijing, Moscow, and
Bosnia as if the reporters were discussing activities taking place in New York,
Peoria, Omaha, or Portland. Every night we receive accurate weather forecasts as
meteorologists intently study the many satellite photographs which show the
latest storm systems and how they will affect our future weather. Satellite
hurricane prediction has saved many lives. This fact alone has made the space
program a worthwhile endeavor.
Space navigation systems have improved safety on both aircraft and shipping
by providing extremely accurate information on position, heading, altitude, and
speed. With the use of the Global Positioning Satellites aircraft can land
within inches of their destinations on any runway without the need of expensive
navigation equipment at the airfield. Ships can avoid known icebergs or
hazardous shorelines even in the roughest of weather.
Future applications will be possible when scientists are able to use the
unique conditions of space such as microgravity, vacuum, and radiation to
perform experiments and determine processes which either can't occur on Earth
due to the laws of physics and chemistry or are too impractical or expensive to
recreate on Earth.
Advanced space technology, created to help people and equipment operate in
the forbidding and harsh environment of space, has made life on Earth more
secure or even possible for all of us. Advances in electronics, medicine,
robotics, computers, miniaturization, and remote sensing have occurred quickly
because of the space program. If there had not been a space program, these
advances would have probably come at a very slow rate if at all.
The space program has contributed greatly to the economic well-being of the
entire world's population and especially the United States. The space program is
a major part of the aerospace industry upon which is based a $32 billion trade
surplus and around a million jobs. NASA created more than 350,000 new jobs from
1986 - 1992 based on technology transferred to the private sector. As the United
States defense budget decreases in the future years the importance of the space
program will increase substantially.
The space program has provided inspiration to the youth of America and the
Earth. The urge to go beyond the limits, to explore what's out there is as old
as humanity. This has led to improved standards of living and an increase in
knowledge. The inspiration of the space exploration has encouraged the youth of
the world to become educated in mathematics, science and other technical skills
thus insuring the future development of our planet. The space program has also
become a natural way to bring the people of the world together with
international cooperation, to pursue a project as a species and not as disparate
groups of human beings. Who knows, perhaps studying the space program may
provide inspiration to you to pursue something beyond your wildest dreams and
imagination.
Why study Space? The answers are as individual and unique as the person
asking the question. Perhaps the reader will develop his or her reason for
studying space which could lead to a lifelong career or a hobby.
© John F. Graham, 1995
Space is defined as that area beyond the Earth's measurable atmosphere which
has very few particles of any size and is flooded with electromagnetic energy.
An atmosphere is the small band of gases surrounding the Earth which is
mandatory for life as we know it. It contains nitrogen, oxygen, argon, water
vapor, carbon dioxide, dust particles, and a group of other minor gases. The
number of particles in the Earth's atmosphere determines how dense it is. A
dense, thick atmosphere with the correct ratio of life supporting gases has a
greater propensity to promote life.
The density of the atmosphere at the Earth's surface is about 1018 particles
per cubic centimeter. That number is 10 with eighteen zeros after it! A cubic
centimeter has approximately the same volume as a quarter of a teaspoon, and
when we speak of particles we mean individual atoms. So, there are 1018
particles in one quarter teaspoon of air at the Earth's surface. As the distance
above the Earth increases the density of the atmosphere decreases. In the
distance from 11.3 kilometers (Km) to 81 kilometers (7 - 50 miles) the density
decreases to 1014 particles per cubic centimeter. 1014 particles sounds like a
great number of particles, but when we say that the Earth's atmosphere at that
point is 1/10000 less than at the surface, life would have a problem of being
sustained. When we reach the distance of 81 to 972 Km ( 50 - 600 miles) the
density decreases to 106 particles per cubic centimeter or about one million
particles per quarter teaspoon of air. Life as we understand it does not exist
at these altitudes. As we depart farther from the Earth to about 972 - 1944 Km (
600 - 1200 miles) the density further decreases to 100 particles per cubic
centimeter. Finally, beyond 1944 Km from the Earth's surface (1200 miles), we
find 1 particle per cubic centimeter or one particle per quarter teaspoon. Using
this fact we can safely say that Space is empty or devoid of matter.
Space may be devoid of matter, but it is flooded with electromagnetic energy.
Electromagnetic energy is defined as energy derived from the energy makers of
outer space. What is an energy maker? An energy maker is defined as a celestial
body or process which readily transforms matter into energy. The closest and
best example of an energy maker is the Sun.
The Sun burns hydrogen transforming it into helium. The energy released by
this process consists of Gamma Rays, X-Rays, Ultraviolet light, visible light,
infrared light, microwaves and radio waves. This collection of energies is known
as the electromagnetic spectrum. The highest energies are in the gamma and x-ray
bands while the lowest are in the radio band; these energies flood outer space.
There are other energy makers besides the Sun.
Other energy makers include healthy young stars, making similar energy like
the Sun; and old stars which approach death by becoming either a nova or a
supernova - in other words the star explodes. The results from these explosions
are white dwarfs, neutron stars, and even black holes. These bodies pour energy
into space. This energy is known as cosmic rays.
With all of this energy concentrated in outer space we should be extremely
grateful for the small, thin atmosphere which surrounds our Earth and protects
the planet's life forms from this flood of energy. Where do the total effects of
all this energy really begin? To answer this question accurately, we must
determine where space begins.
CHAPTER 3 -- WHERE DOES SPACE BEGIN?
© John F. Graham, 1995
Answering this question depends upon with whom you are discussing the
subject. A doctor would state that outer space begins when the human body can no
longer survive in the atmosphere. A propulsion engineer might say that space
begins when a jet engine which needs air from the atmosphere to function can no
longer operate. An aerodynamic engineer might say that space begins when there
is not enough of an atmosphere for an aircraft's control surfaces to operate the
craft. A bureaucratic agency might have one definition and an international
organization may have another. There is no set standard as to where space
begins. We could set our own standard or create our own definition as to where
we think space begins. Let's look at a few definitions from the experts.
Obviously space does not start at the surface of the Earth because that is
where our atmosphere pragmatically begins. If we climb to about 3000 meters (m)
(10000 feet) we find that the amount of oxygen present and the pressure with
which this oxygen enters our bodies is really not enough to keep a human body
operating efficiently. Immediately a number of you are thinking that a number of
people live above 3000 m in mountainous countries and they can still function.
LaPaz, Bolivia; Quito, Equador; Katmandu, Nepal; and Leadville, Colorado are a
few examples of where people live today and they seem to function very well.
They have become acclimatized to this altitude and their bodies have adjusted to
the sparse amount of oxygen. Could a flatlander arrive in LaPaz and immediately
start functioning with the same efficiency as a native Bolivian? Probably not.
The Federal Aviation Administration has dictated a regulation that whenever
pilots fly above 3000 m ( 10000 feet) they will have supplemental oxygen
available for them and their passengers. The United States Air Force goes a
little further and states that their pilots will be on oxygen above 10,000 feet
cabin pressure altitude. As altitude increases, the need for supplemental oxygen
also increases.
At 5309 m (18000 feet) one half of the atmosphere is below the persons in an
aircraft. At this point a pilot who is at this cabin altitude must be on oxygen
or a condition known as hypoxia (lack of oxygen to the blood or circulatory
system) will render the aviator unconscious within 30 minutes.
At 16,000 m (16 Km or nine miles) the use of supplemental oxygen fails as a
sustainer for human life. At this altitude the combined pressure of carbon
dioxide and water vapor in the lungs equals the outside atmospheric pressure and
supplemental oxygen alone cannot reach the blood without additional pressure.
Therefore, the pilot and passengers must be in a pressurized cabin or if the
pilot is in a smaller craft he or she must wear a pressure suit.
At 20 Km (12 miles) the outside atmospheric pressure equals the vapor
pressure of the human body or about 47 millimeters of mercury. In this
environment bubbles of water and other gases begin to form in the body. The
bodily fluids begin to literally boil. A pressurized cabin or a pressure suit
will protect all occupants of an aircraft at this altitude from this violent
condition.
At 24 Km (15 miles) an aircraft's pressurization system no longer functions
economically. There is so little oxygen and nitrogen at this altitude that it
cannot be compressed to protect the pilot, crew, or passengers from the outside
elements. Also at this altitude, the ozone layer begins to form in the
atmosphere. Even though ozone consists of three atoms of oxygen per molecule,
this substance is poisonous to the human body and compressing ozone would poison
the cabin and its occupants. At this altitude the cabin or space suit must have
its own pressure and oxygen independent of the outside atmosphere. For the human
body space begins at this point because above this altitude a human must carry
everything in order for the body to survive. This is probably the doctor's
definition of where space begins.
At 32 Km ( 20 miles) turbojets can no longer function. Used today as a means
of propulsion for all modern jet aircraft, turbojets intake air and compress it
by means of fans to mix with fuel for combustion. At 32 Km there is not enough
air to compress for mixing with the fuel; above this altitude aircraft must use
ramjets. A ramjet operates similar to a turbojet except that a ram jet
compresses air using supersonic shockwaves rather than fans. The speed of the
air going through the shockwave compresses it much more efficiently than the
mechanical turbojet. At 45 Km (28 miles) there is not enough air even for a
ramjet to operate. Above this altitude a propulsion system needs to provide its
own oxygen, also known as oxidizer, as well as fuel. This type of craft is
called a rocket. To a propulsion engineer space begins above this altitude.
At 81 KM (50 miles) one government agency, the United States Department of
Defense says that space begins because it awards all pilots who fly above this
altitude astronaut wings. This group not only includes all the people who have
flown the space shuttle and various other craft into space, but also the X-15
pilots who flew above this altitude.
At 100 Km ( 62 miles) aerodynamic forces are no longer effective enough to
move the various control surfaces to control an aircraft. The rudder, the
aileron, and the elevator are no longer effective because there is not enough
atmosphere for either lift or drag the two major aerodynamic forces to be
effective. At this altitude space is dark; the stars no longer shimmer, but are
hard points of light. Other than various fans and other electronic equipment
there is no sound; no sonic booms, no explosions, or no shockwaves can be heard
in space. One of the best illustrations of this phenomenon is presented in
Stanley Kubrick's movie 2001 an adaption of Arthur C. Clarke's novel. The
astronaut Dave has been trapped outside his craft by the maniac computer HAL. In
order to get back into the spacecraft, Dave has to open an emergency hatch and
explode the door from his pod propelling him into the spacecraft where he closes
the hatch by pulling the emergency hatch lever. The camera records the explosion
and shows Dave tumbling into the emergency hatch area, but the viewer hears no
sound until Dave pulls the emergency hatch closing lever and the screen floods
with sounds of closing hatches and rushing air. There is not enough air in space
to create sound.
Surely you say, some international body must have declared where space
begins. International law states that there is no definitive point where the
atmosphere ends and space begins. The major space powers accept the following
definition: Space begins at " the lowest perigee attained by orbiting space
vehicles..."
Perigee is the closest approach point to the Earth in an elliptical orbit. A
potential challenge to this definition occurred in 1976 when eight equatorial
nations issued declarations of sovereignty over the geosynchronous orbit belt
which lies 35862 kilometers above the equator. Columbia, Equador, Brazil,
People's Republic of the Congo, Zaire, Kenya, Uganda, and Indonesia also stated
that they would defend such areas. But in 1980 the United Nations determined
that such claims were null and void because Outer space is international
territory.
Where does space begin? It depends on the reference point. Perhaps you would
like to choose your own frame of reference where space begins or choose one of
the various definitions selected by the experts. Your definition is just as
viable and as accurate as theirs.
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