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Probaway - Comet

Tunguska

1908

© 1994 by Charles Scamahorn

Probaway—Comet shows you how a comet struck the Earth in 1908 and why it or another comet could not destroy Life on Earth.

In Siberia on June 30, 1908 thousands of people saw a huge object streak rapidly and brilliantly through the morning sky and then apparently reverse direction and descend straight down toward Tunguska. Several people were less than twenty miles from where it fell and reported a roar like cannons, followed by a swift, foul smelling wind, which left them unconscious. Upon regaining consciousness they found themselves to be uninjured and later when people went to the Tunguska site they discovered a vast area of pine trees flattened down and pointing radially outward from the center. The trees had scorched bark, appearing as if they had caught fire but these scorched trees had not burned. At the very center of the devastated area they found the trees shorn of their limbs but still standing vertically. This assemblage of weird facts has remained without a satisfactory explanation until now.

I begin my explanation with the modern spectroscopic analysis of comets which shows them to be made of frozen water, like dirty snowballs or giant icebergs. But I suggest that if they were constituted of the same chemical materials but much less dense than snowballs, formed more like giant fluffy snowflakes, then when such an object struck the Earth's atmosphere at 20,000 mph, at a raking angle, the people below would observe exactly the effects seen at Tunguska. It would progress like this: First the bottom of the falling comet, while raking the upper atmosphere, would form a brilliantly glowing sheet. Moments later the thicker cross-sectioned middle would strike further along its inertial path and compress into a thicker and wider sheet of rapidly decelerating incandescent steam and finally the thin topmost portion would swiftly pass over this slowed middle portion and strike. This topmost portion of the comet would strike furthest along the path but being thiner this portion would burn up more quickly. Thus the slowed, but thicker, central portion would still be glowing after the rapidly moving top had passed it by, and burnt itself up. This sequence of events would give the viewers below the seemingly inexplicable appearance of the swiftly moving fireball reversing its direction.

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A minute or so after the fireball had stopped glowing, the forest below appears to have been struck by a near vertical wind. I estimate the wind to have been about 200 mph because of the way the limbs were ripped from the trees. But the wind didn't last very long. If it had, the surrounding trees would have been picked up and hurled into a dense ring of jumbled lumber around the periphery. From this estimated wind velocity and the estimated velocity of the comet, the comet's cross-sectional mass can be roughly calculated. To accelerate the air above the site to about 200 mph by mixing it with my postulated comet moving about 20,000 mph would require the comet's cross-sectional mass to be roughly 1/100 that of the weight of the air above the site. That is equivalent in cross-sectional mass to about four inches of liquid water. Thus I estimate the bulk of the Tunguska comet, and probably all comets, to be very tenuous and less dense than air at sea level. They would be space filled-crystals called aerogels. The Tunguska object itself had to be of a fairly uniform composition and contain no large solid or even liquid objects because nothing was observed to continue flying forward from its fireball.

The trees in the forest directly below the fireball were scorched by the incandescent heat of the fireball but any resultant fire was quenched. Apparently this downward blast of air was saturated with water and perhaps carbon dioxide. The carbon dioxide may have helped extinguish the fires and it may account for the people nearby being rendered temporarily unconscious without being injured. The foul smell may have been the comet itself or more likely that of the broiled forest. The people were revived a few minutes later, before they died of suffication, by the fresh air that would have blown in normally.

Another suggestion of the delicate nature of comets is in the shallowness of many craters on the Moon. I would expect that in a lighter gravity field, such as found on the Moon or on asteroids, the walls of craters hit by hard objects would be quite steep, even steeper than the walls of Meteor Crater in Arizona. But the walls of nearly all of them appear very shallow as if puffed out by very fluffy objects similar to my postulated Tunguska comet.

A density test is in order and the Shoemaker-Levy comet striking Jupiter in July 1994 provided one. It was reported by astronomers to be made up of some 20 parts each of which was projected to yield 250,000 megatons of energy. If my theory is correct the energy yield on Jupiter would be closer to one megaton. The difference in magnitude of effect ought to be similar to the difference between a ping pong ball and a city bus falling out of the sky. That amount of difference of effect ought to be discernible, even at the great distance to Jupiter. The observed magnitude of the Jupiter impacts suggest that before being broken up by Jupiter's gravity they were a cluster of gravitationally bound solid asteroids and dust visiting from the Asteroid belt and not comets from trans-solar space. Giant asteroid strikes on Earth are Life threatening and rare, but comets, at least pieces of comets are more common. Fortunately, comets would only kill those individuals unfortunate enough to be directly hit by them.



[ Some further comments on life-threatening impacts.]

The Life On Earth

The Precursor Events To Our Life.

The great theological questions are, "Where did life come from? Why are we here? Where will we go?" There have been many answers to those questions, but most of them are just interesting stories which offer little or no testable proofs for their assertions. There are an infinite number of such stories in the Universal Library, but only one historical sequence of events which led to present Earth. Let me offer a plausible scenario of that exact sequence which I think will offer some modicum of provable denyability.

About five billion years ago our solar system formed by the accumulations of gas and small particles because of gravitational effects on the preexisting materials. After a time there were a large number of proto planetesimals swirling and jostling around the newly forming sun. These collided occasionally and coalesced to form a smaller number of planets, one of which became known to us as Earth. Another one, let me call it Asteroidus, formed between Mars and Jupiter, but after it had cooled for a while and looked like a normal rocky planet such as Mars, it was struck by another approximately similar sized object in a highly eccentric orbit. The rogue wandering of the planetesimal was probably caused by some interaction with Jupiter, the usual villain in such cases. The impact of these two bodies was so great that it shattered Asteroidus into what we now call the Asteroid belt, and also into many non-circular-orbit sun-orbiting rocks, some of which formed into a moon sized object which wandered for a short time and then struck the early-Earth with a terrific glancing blow. This blow splashed some debris into a solar orbit, but also it left many chunks in various Earth orbits. These chunks interacted, and when they were pulled together by their own gravity, coupled with some interactions with the atmosphere and the tidal friction of Earth's ocean they formed our Moon. After the impact the Earth's surface was molten hot and any volatile materials like water were evaporated into a gaseous atmosphere. Highly volatile hydrogen gas and helium gas probably evaporated completely off of the Earth just as it did off of the moon.

How The Earth Became A Livable Environment

As the various chunks of debris in solar orbit are swept up by the planets there are fewer impacts and less frequent big impacts and the surface of Earth can cool. When the Earth is cool enough the less volatile components of the atmosphere, such as water, can precipitate out and thus our ocean can start forming. At the beginning of the ocean's formation there would have been little more than small streams and ponds at various low points. The barometric pressure in these ponds would be great as the liquid pressure presently is at the bottom of the oceans, the only difference being that the ocean of water above the pond was in gaseous form.

Darwin's Warm Little Pond

Thus, we have something similar to Charles Darwin's warm little pond, which he seems to have thought to have been something more akin to the present surface. Present day mid-oceanic-ridge hydrothermal vents, located some 12,000 feet below the ocean surface offer a closer approximation of that early situation but by present day surface standards it would be lethally hot. Some present day deep oceanic or deep rock thermophilic life forms might have found those earliest environments quite pleasant.

The present type of oceanic-hydrothermal type vents may not have existed at that time because Earth's inner-core radioactive processes may not have been functioning convectively yet but there would probably have been other types of venting and a great variety of chemical and mechanical interactions available for alternate combinations of molecular soups. Each stream and the pond at the end of it would offer a unique set of chemical possibilities and some of them worked to form life like entities. When more water precipitated out the oceans would consolidate and the new life forms could spread world wide and interact to form even more complex chemical arrangements. In all of this I have not strayed far from standard current scientific life-creation scenarios. The early moments of life were proably self-assembly on the surfaces of crystal-like materials and later cell surface formation by the forcing out of electrically charged metabolized materials.

Life Exists On Earth

One thing is certain, however, life exists on Earth and therefore either it was created here, or it was created somewhere else and imported. If it was imported it had to form at that other place by some similar process and then be ejected from there and then be transported across vast distances of the hostile environment of space and time and then endure the very hostile but different problem of reentry into Earth's atmosphere. If life can be created elsewhere, by some similar processes, it can be created here on Earth and we can leave out the difficult transportation problems of getting from there to here. Thus, life being created right here on Earth becomes the most plausible explanation. Primitive life is a natural phenomena and when the conditions are just right -- it happens; and when it once exists it evolves via natural selection to fit the various environments. If more advanced life forms reached Earth in the distant past there would not have been the four billion year extremely slow evolution to multicellular life forms that is visible in the geological record.

What Will Life Evolve To Become?

All well and good, but occasionally a big surprise impact, a "BIG BOOM" and Life on Earth is exterminated. When the first life formed on Earth there were probably plenty big asteroids still drifting around. All that was needed to exterminate life, at that time, was an energy input into the planet's atmosphere big enough to evaporate the oceans. And as the oceans were still small, and big asteroids, and gigantic eruptions, still common, life may have formed many times and been exterminated many times by some violent process. We are simply the decedents of the last great life forming event and we haven't been exterminated yet. There are plenty of well known possibilities: collisions with giant asteroids, moons, or planets, exploding stars with lethal radiation, and fast moving gas clouds heating or poisoning the Earth, all of them offering the potential to exterminate life on Earth and last but by no means the least, the most inexorable killer of them all ... time ... vast stretches of TIME. Given enough time, even tiny events can become killers. Of course humans themselves have quite a record of extermination of species but to exterminate all life right down to the thermophilic life forms is at present well beyond our ability.

What Is The End Of Life?

We must realize that in the long run something will exterminate all life on Earth once again. Maybe we will have to wait a few billion years for the Sun to burn-out and destroy us. Whatever it is, eventually there is an end, ready or not, eventually it will come.

So, until then, we should enjoy ourselves. This is our time to live. From Life's point of view our task is obvious, to live and reproduce. From our point of view, the goal of our lives is to participate in the situations which present themselves to us.


Liability disclaimer statement: These Probaways contain new and unique information that has been created, tested and retested by me alone. You must approach these findings and materials very carefully as your results may differ greatly from my experience and I can offer no recompensation of any kind for any injuries.

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