The
Earliest Space Exploration
By Boris Vasilev
The
earliest space explorers were simply inquisitive people
who looked up into the night sky thousands of years ago
and wondered, "what is it and how does it work?"
Early human understanding of the mysterious firmament above
was based on mythology and superstition. Most every early
culture had a simple yet elegant story of how the heavens
came into being.
It
wasn't until the Greek renascence that some Greek philosophers
began to move away from supernatural explanation of the
world to a more rational view of how the world and heavens
worked. Some time between 700 - 480 B.C. a Greek philosopher
known as Thales of Melitas proposed the philosophical concept
of rationalism. It was the notion that the world around
us could be explained and understood by humans. Until that
time the Greeks view of the heaven and earth were based
on a belief in a pantheon of Greek Gods who's actions were
responsible for all that was.
Once
the notion of rationalism started to take hold many Greek
philosophers began to come up with alternate explanations
for the inner workings of the sky above. Eudoxus (400 B.C.)
proposed that the Earth sat motionless at the center of
the heavens and that the stars were attached to an outer
sphere. As the sphere rotated on its axes people on earth
would observe the rising and setting of the stars and planets.
As
can be seen, not all of the early attempts at explaining
the world in rational terms were successful. Most people
at that time thought that the world was flat. However the
Greek philosopher Aristotle observed that the earth cast
a curved shadow on the moon and that the Earth must therefore
be a sphere. The philosopher Eratosthenes later used simple
mathematics to calculate the circumference of the earth
to be about 24,840 miles. The actual circumference is around
24,900.
Other
early Greek philosophers were far more bold in their ideas.
Aristarchus proposed a heliocentric model for the universe
.
He believed that the earth was simply one of several planets
that revolved around the sun. Until this time the Geocentric
model of the universe was the most widely accepted. Another
Greek Philosopher, Hipparchus (150 B.C. - pictured left)
has been called the greatest astronomer of ancient times.
He accurately estimated the distance from the Earth to the
moon . He also created the most complete star catalogue
to that time.
Over
time the greatness of Greek culture was superceded by the
Roman empire. During this time the works of the early Greek
culture began to slip away. As the Roman empier, weary and
old, started it's decline the Greek knowledge was lost and
all of Europe slipped into a dark age who's grip held firm
until the 1500's.
As
Europe had succumbed to the strife and conflict of the middle
ages an Arab ruler named Harun-al-Rashid set up a library
of ancient works later be called the House of Wisdom. Arab
scholars gathered there bringing rescued copies of many
of the ancient Greek works which were translated into Arabic.
As a result, much of the wisdom and knowledge of the Greeks,
although lost to Europe was not lost to the world.
Around
1500 A.D. the shadow of the dark ages was waning and the
Greek works preserved in Arab started making their way back
into Europe. This European Renaisance gave witness to some
of the most fundamentally important people and works that
western culture as ever seen.
One such individual was Nicholaus Copernicus (pictured right).
He
perfected and championed the heliocentric view of the solar
system. His work went largely unrecognized. The heliocentric
view of the heavens was deemed heretical by the church establishment
of the time. Starting in 1576 an astronomer named Tycho
Brahe started to measure the changing positions of the planets.
His observations laid the foundation for one of the most
important scientific discoveries of all time.
In
1600 a man named Johann Kepler used Tycho's observations
to create his laws of planetary motion. Our modern understanding
of our solar system would not be possible without Keplers
laws of planetary motion.
In
1564 one of the greatest astronomers to ever have lived
was born, Galileo Galilei (pictured left)
.
In 1609 he invented the first refracting telescope. With
it he began observing the sun and planets in our solar system
with a level of detail that no human before him had ever
seen. His observations proved beyond a shadow of a doubt
that The Copernican view of the solar system was true.
However,
just like Copernicus before him, his views were deemed heretical
by the church and he was forced to publicly recant what
he knew to be the truth.
Building
on Galileo's discoveries was the now legendary Isaac Newton
(pictured right)
.
He wondered what forces were at work to keep the planets
in their orbits around the sun and the moon from flying
away from the Earth. In the process he came up with Newton's
three laws of motion. The third is most widely known: For
every action there is an equal and opposite reaction. He
also went on to form the basis for our understanding of
gravity as the fundamental force binding the heavens together.
After
a intellectual journey of over 2000 years the stage was
set and the fundamental tools acquired for the amazing events
to come in space exploration. Every adventure into space
that humankind undertakes today would not be possible if
it were not for those great thinkers and dreamers that filled
our past. It is to those that came before us that we owe
so much to. They were the first true space explorers.
