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Science, Theory, & Paradigm Shifts
Paradigm Shifts I
A COMET TALE: The Ort Cloud
The Ort Cloud is an icy debris field left over from the creation of
our solar system.
• At the edge of solar system
• Half way to nearest star
• Billions of individual objects
• Object 100 miles (163.93 km) in diameter
A COMET TALE: …The Ort Cloud
This icy debris field contains
the remains of the primordial
dust cloud that collapsed and
gave birth to our sun.
• Through a process called accretion,
stars are forged and planets
constructed.
• All of the stuff in our solar system
originated from this stellar nursery.
• The ort cloud contains the left-over
raw materials used in this creative
process.
A COMET TALE: The Ort Cloud
Our star (the sun) generates a
solar wind containing charged
particles and other gasses.
• Solar wind interacts with interstellar
gas and dust creating a “bow shock”
• The bow shock region of space is
considered the “city limit” of our solar
system and the beginning of interstellar space.
• The ort cloud and everything in it lies
beyond the bow shock region of
space.
A COMET TALE: …The Ort Cloud
Occasionally a nearby star
disturbs the ort cloud, sending
objects hurtling toward our
sun.
• Ort cloud objects are disturbed
by the gravity of a neighboring
star. Some fall toward our sun.
• As these objects come closer
to the Sun, it’s solar wind will
heat the object and cause it to
melt.
A COMET TALE: …The Ort Cloud
As object melts, a tail of debris
forms, creating a comet.
• A comet forms as a result of
debris emitted by the object as
it melts.
• Solar wind pushes the debris
away from the object forming a
tail.
• Tail can extend for hundreds of
millions of miles and is often
visible from earth.
A COMET TALE: Messengers of the gods.
The ancients viewed comets as messengers of the gods.
The ancients are right about comets being messengers:
• What our solar system is made of…
• Primordial conditions of our solar system
• Where all the water came from
The ancients are wrong about comets being messengers:
• Omens that influence the lives of individuals or groups of people…
• Telling of the fate of kingdoms or crops…
A COMET TALE: …Messengers of the gods.
A comet lights the sky…
• Once every ten years on avg
• Some seen in daylight
• Tails can fill the sky
• Suddenly appear and disappear
To the ancients, their inability to predict
the appearance and disappearance of
comets led to a common interpretation
that comets were significant.
Often comets were viewed as
messengers of the gods.
A COMET TALE: …Messengers of the gods.
Throughout history, people
have tried explaining comets.
• More than 2200 years ago the
ancient Chinese classified comets
into 29 separate types.
• The shapes observed by the ancients
were striking enough to be recorded
in myth.
• Comets were gods in the sky, and
they were recorded globally by many
cultures.
A COMET TALE: …Messengers of the gods.
Comets have been described
in the mythology of many
cultures as metaphors:
• Comet as a Dragon or Cyclops
• Comet as the sword “Excalibur”
A COMET TALE: …Messengers of the gods.
Natural science tells us that comets are natural…
…the ancients understood comets as being supernatural.
…even today, many people have paranormal beliefs about comets.
• Why do comets seem so important?
• Why the appeal to the supernatural?
A COMET TALE: My good sign, your bad sign.
In 1066 William the Conqueror
saw a comet…
•
Saw it as a sign foretelling victory.
•
Invaded England after seeing comet.
•
Commissioned a tapestry of battle.
•
Comet is shown in the tapestry.
King William I saw the comet as a sign
from God that he would be victorious.
King Herald saw the comet as a sign from
God that his kingdom was doomed.
A COMET TALE: …My good sign, your bad sign.
In 1219, Genghis Khan saw a
comet…
• Saw it as a message to fulfill destiny
• Waged war across Asia and Europe
• He fulfilled his destiny.
To the Mongols the comet symbolized
victory.
To the vanquished the it symbolized
death and defeat.
A COMET TALE: A Natural Explanation
In 1680 Sir Isaac Newton saw
a comet…
• He saw a comet from Oct-Nov 1691
before it disappeared
• He saw another comet from mid DecMar 1682 before it disappeared.
Sir Newton asked a profoundly simple
question about what he had recorded:
“Were these two events caused by a
single comet or by two?”
A COMET TALE: A Natural Explanation
In 1682 Sir Isaac Newton
discovered gravity…
• How did he make this discovery?
• Many of us learned that he made the
discovery while sitting under an apple
tree when an apple fell onto his head.
• Newton got the idea of gravity from
such personal experiences but he
didn’t discover it that way.
• Newton discovered gravity by
studying the behavior of a very
famous comet.
A COMET TALE: A Natural Explanation
Was it one comet or two?
•
Newton assumed that both events were
caused by a single comet
•
A single comet would disappear and reappear
if it were in orbit around the sun just like the
planets.
•
By plotting the course of the comet across the
sky, Newton found evidence to support his
assumptions
•
Newton observed that the comets orbit
appeared to bend as it approached the sun.
•
The bent orbit of the comet meant that an
unseen force was changing the course of the
comet and the closer the comet was to the sun
the stronger the force appeared to be.
He called this unseen force: gravity.
A COMET TALE: A Natural Explanation
The power of a natural
explanation for comets…
Newton had a new theory that comets were natural.
•
Comets have closed circular paths just like
planets.
•
A comet with a certain orbit will one day return.
•
The return of such a comet can be predicted
by observing its path around the sun over time.
•
If Newton could predict the return of a comet
this would prove that it was natural.
Newton with the help of his friend
Edmond Halley set out to predict the
return date of the comet they saw.
A COMET TALE: A Natural Explanation
Predicting the return of a
comet...
Newton and Halley compiled tables of all comet
observations that they could find in human memory.
•
They looked for patterns that repeated
throughout history...
•
Halley found three references to comets
whose descriptions were identical...
•
One in 1591, 1607, & 1682.
•
Each report was separated by 75 years.
Convinced that these references were the
same comet they had observed, they
made a bold prediction that the comet
would return again in late 1758.
A COMET TALE: A Natural Explanation
An extraordinary display of
scientific bravado...
Neither Isaac or Halley lived to see if their prediction
was right...
•
In 1758...a comet was observed in the sky
•
The comet was met with jubilation...
•
The comet lost its supernatural cause
•
This event was viewed as a triumph of science
over the supernatural.
•
The comet was named
"Halley's Comet" after the man
who first saw the recurring
pattern in the historical data.
A COMET TALE: A Natural Explanation
Truth trumps fiction...
When scholars look further back through historical
records, Halley's comet was found to appear like
clockwork.
•
Genghis Khan saw a comet...it was not a
personal message...it was Halley's comet.
•
King William saw a comet...it was not a sign of
his victory...it was Halley's comet.
For the first time, there was
compelling evidence that
comets were natural.
A COMET TALE: A Natural Explanation
Comets are natural things...
Comets became as predictable as the planets and
stars. But...
•
Many during Newton's time did not understand
his theory; thus, comets remained a source of
superstition for some...
•
Today, a mountain of evidence exist telling us
that comets are basically dirty snowballs and
yet, paranormal belief about comets still exist.
The Heaven's Gate cult is a
recent example of modern
paranormal belief about
comets.
A COMET TALE: A Natural Explanation
Scientific discoveries change
the way we think about
nature...
In the realm of science, Newton's laws of gravitation
were so profound and useful that these laws
became the foundation of a new cosmology.
•
Newton's theory of gravitation allowed scientist
to predict the existence of undiscovered
planets in our solar system.
•
Newton's discovery worked so well, that it
became standard practice for all scientist who
studied the cosmos.
The wide-spread adoption of Newtons theory
by other scientist is called a PARADIGM
SHIFT.
•