Re: Meteor Program

From: glenn morton (
Date: Wed Aug 02 2000 - 13:54:12 EDT

  • Next message: glenn morton: "Meteor Program"

    Allen wrote:

    >All asteroid impacts creating impact craters are the same as un-contained
    >underground blasts. These asteroids are so big that the air does not cause
    >enough compression. It is only after entering the ground that critical
    mass is
    >reached. The blast of an un-contained underground blast is even less
    >destructive than a surface blast. The bright flash is fully contained
    >underground, so instant fires cannot happen. The shock wave is directed
    >entirely upward. A much diminished shock wave does follow along on the
    >Most of the energy of the blast is absorbed into moving the earth outward


    I will re-post what I posted before about all the different killing
    mechanisms of a major impact crater. Even if most of the energy is directed
    upward, enough goes around the earth to kill everything, or nearly
    everything. Maybe you should try to answer this data, which you didn't last
    time and apparently you still haven't incorporated it into your thinking.
    Here is what I posted before. Please deal with each of these killing
    mechanisms before you say that the flood was caused by such an event.


            "Computer models of explosions with energies of 1,000 megatons--about 20
    times the energy of the largest nuclear bombs but only 1/100,000 the energy
    of the KT impact--have shown that the fireball never reaches pressure
    equilibrium with the surrounding atmosphere. Instead, as the fireball
    expands to altitudes where the density of the atmosphere declines
    significantly, its rise accelerates and the gas leaves the atmosphere at
    velocities fast enough to escape the earth's gravitational field. The
    fireball from an even greater asteroid impact would simply burst out the
    top of the atmosphere, carrying any entrained ejecta with it, sending the
    material into orbits that could carry it anywhere on the earth."
            "The impact of a comet-size body on the earth, creating a crater 150
    kilometers in diameter, would clearly kill everything within sight of the
    fireball. Researchers are refining their understanding of the means by
    which an impact would also trigger extinction worldwide. Mechanisms
    proposed include darkness, cold, fire, acid rain and greenhouse heat.
            "In our original paper, we proposed that impact-generated dust caused
    global darkness that resulted in extinctions. According to computer
    simulations made in 1980 by Richard P. Turco of R&D Associates, O. Brian
    Toon, of the National Aeronautics and Space Administration and their
    colleagues, dust lofted into the atmosphere by the impact of a 10-kilometer
    object would block so much light that for months you would literally be
    unable to see your hand in front of your face.
            "Without sunlight, plant photosynthesis would stop. Food chains everywhere
    would collapse. The darkness would also produce extremely cold
    temperatures, a condition termed impact winter. (After considering the
    effects of the impact, Turco, Toon and their colleagues went on to study
    nuclear winter, a related phenomenon as capable of producing mass
    extinctions today as impact winter was 65 million years ago.)
            "In 1981 Cesare Emilliani of the University of Miami, Eric Krause of the
    University of Colorado and Eugene M. Shoemaker of the USGS pointed out that
    an oceanic impact would loft not only rock dust but also water vapor into
    the atmosphere. The vapor, trapping the earth's heat, would stay aloft much
    longer than the dust, and so the impact winter would be followed by
    greenhouse warming. More recently John D. O'Keefe and Thomas J. Ahrens of
    the California Institute of Technology have suggested that the impact might
    have occurred in a limestone area, releasing large volumes of carbon
    dioxide, another greenhouse gas. Many plants and animals that survived the
    extreme cold of impact winter could well have been killed by a subsequent
    period of extreme heat.
            "Meanwhile John S. Lewis, G. Hampton Watkins, Hyman Hartman and Ronald G.
    Prinn of the Massachusetts Institute of Technology have calculated that
    shock heating of the atmosphere during impact would raise temperatures high
    enough for the oxygen and nitrogen to combine. The resulting nitrous oxide
    would eventually rain out of the air as nitric acid--an acid rain with a
    vengeance. This mechanism may well explain the widespread extinction of
    marine invertebrate plants and animals, whose calcium carbonate shells are
    soluble in acidic water.
            "Another killing mechanism came to light when Wendy Wolbach, Ian Gilmore
    and Edward Anders of the University of Chicago discovered large amounts of
    soot in the KT boundary clay. If the clay had been laid down in a few years
    or less, the amount of soot in the boundary would indicate a sudden burning
    of vegetation equivalent to half of the world's current forests. Jay Meos
    of the University of Arizona and his colleagues have calculated that
    infrared radiation from ejecta heated to incandescence while reentering the
    atmosphere could have ignited fires around the globe." Walter Alvarez and
    Frank Asaro, "An Extraterrestrial Impact," Scientific American, Oct. 1990,
    p. 80-82

    Then Allen asked:
    >Is this all accounted for in your program?

    My program calculated flightpath the megatonnage yield and crater or
    airblast size (although right now it underestimates the airblast size).

    Foundation, Fall and Flood
    Adam, Apes and Anthropology

    Lots of information on creation/evolution

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