> Steve Willner wrote:
> > In article <1141439913.023059.27090@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
> > dlham@xxxxxxxxxxx writes:
> > > The reoccuring glacial periods are strong evidence that our sun is a
> > > variable star that expands and contracts in fairly regular cycles.
> > What is the mechanism causing this supposed solar variability?
About four and one half billion years ago our protosun was slowly
collapsing under the force of its gravity. As it did this, due to the
immense compression caused by gravity it became extremely hot. Millions
of degrees centigrade. The more compact it got the hotter it got. It
was not alone in the sky, it was part of a community of stars and
protostars. It lay in the outer regions of our galaxy, the Milky Way.
It was being swept around the galaxy, along with its neighbors, at the
tremendous speed of over 500,000 miles per hour. So far it had no
satellites, (planets, moons, etc.) it's gravity had sucked in most of
the star dust from its vicinity for hundreds of millions of miles in
It was getting close to the temperature and pressure required for a
nuclear fusion reaction to occur. The protosun was like a giant nuclear
hydrogen bomb waiting to be detonated. When this tremendous event
finally did occur the nuclear fusion reactions started up, in the
hottest most dense area of the Sun.
Tremendous amounts of radiant nuclear energy were suddenly created in
the innards of the Sun. All of this newly released energy caused a
sudden sustained violent increase in the pressure and temperature of
the Sun creating tremendous chain reactions throughout its core region.
These reactions did not just cause the star to began shining. It caused
the Sun to violently explode, expanding to many times its former size.
The explosion sent its matter hurtling at great speed outward in every
direction in all sizes and speeds, both gases and molten solids, from
the size of small particles to the size of the giant planets. Some of
it was hurled out at such a great velocity that it was lost forever to
other regions of the galaxy.
Much of the debris eventually fell back, into the speeding Sun, if its
trajectory was just right. Other debris, after it had expended its
outward energy and had not broken free of the Sun's gravity, began to
fall back toward the Sun. It fell back toward the Sun, but due to the
Sun's great galactic speed and changing position always missed the Sun.
This is the matter that became the planets, moons, comets, asteroids of
our solar system. They are the survivors. It is like a skeet shooter
who always aims directly at the clay pigeon, not allowing for a lead.
His shot will never strike the pigeon simply because it will always
have moved by the time the shot gets there. This is the basis on how
our solar system works. It was a time of tremendous chaos in the solar
vicinity, with all the matter rushing back toward the Sun from every
direction crashing into each other and falling back into the Sun.
After the initial explosion, as the Sun expanded outwards, it began to
cool. As it cooled the area that a fusion reaction could take place
became smaller and smaller. Some of the fusion reaction began to shut
down. The expansion eventually came to a halt as the fusion energy was
no longer powerful enough to sustain the outward momentum. Finally the
Sun began to contract. This at first stabilized the fusion reaction and
then as the gravitational contraction of the Sun continued, the area of
the reaction again began to increase. When the Sun had contracted to
the point where the area of reaction was again very large, the Sun
again expanded and exploded outward with tremendous force sending more
matter hurling out into space.
This time however the expansion and explosion was not as powerful as
the first event. This sequence of events happened again and again, each
time the explosion was weaker and the expansion and contraction not as
great as the previous event. This pulsation of the Sun gradually
diminished after millions of Earth years, until it finally stabilized
and became a mature star whose periodic variability spanned thousands
of years. This periodic expansion and contraction is simply the
balancing act of the Sun's gravitational and nuclear fusion forces.
Eventually out of all this chaos and turmoil our orderly solar system
began to emerge. The Sun had slowly settled down from its tremendous
expansions and contractions of earlier times.
The periodic expansion and contraction continues today at a very
attenuated pace, causing our regularly reoccurring ice ages. The
reoccuring glacial ages are about the only phenomena that spans a
enough time to offer evidence of the long cycle variability of the sun.
Scientists have also determined that the glaciers of our last ice age
began receding at both poles simultaneously. This is additional
evidence that the sun's variable solar radiation is the cause of the
major glacial ages.
Ref: The Mind of Mankind - Chapt.12 - The Birth of the Earth
> Don Hamilton
> > Steve Willner Phone 617-495-7123
> > Cambridge, MA 02138 USA
> > (Please email your reply if you want to be sure I see it; include a
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