- It is happening for "no apparent
reasons", scientists say, but the comet Schwassmann-Wachmann 3 has
been rapidly breaking apart, provoking another round of second-guessing
by astronomers.
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- The images above, captured by NASA's
Hubble Space Telescope, are the best pictures yet of an event that has
astronomers scratching their heads. The comet Schwassmann-Wachmann 3,
otherwise known as Comet 73P, is disintegrating in front of their eyes.
But what is the cause of this extraordinary event? Not one of the theoretical
surmises offered so far has satisfied the community of astronomers as
a whole. From all standard vantage points such an event presents inherent--some
would say insurmountable--dilemmas.
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- Schwassmann-Wachmann 3, first observed
in 1930 and named after its two German discoverers, completes an orbit
every 5.4 years. Following its discovery it was little more than a footnote
in comet science until 1995. The first appearance of the comet that year
was so bright that astronomers hailed it as a new comet. But as it turned
out, the "newcomer" was Schwassmann-Wachmann 3, presenting itself
in more glorious dress than ever before, despite the fact that conditions
were not favorable. It was 150 million miles away, but shining hundreds
of times more brightly than expected.
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- In early 1996 astronomers discovered
that the comet had fragmented into at least three pieces, an occurrence
clearly linked to the spectacular brightening, though no one could say
what caused the event. It also appeared as if one or more of the pieces
was breaking into secondary fragments.
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- When the comet returned in 2000 it was
again brighter than expected, with indications that the disintegration
was continuing--or even accelerating. And now, with its most recent appearance,
the best Hubble images show dozens of fragments, suggesting the possibility
of complete dissolution in a single remaining passage around the Sun.
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- Meanwhile, the "explanations"
proposed for the comet's catastrophic fate can only diminish confidence
in today's comet science. Even in the face of falsifying discoveries,
the specialists appear unwilling to reconsider their theoretical starting
point. One astronomer, from the Sydney Observatory, offered this explanation
of the comet's fragmentation: "It's like pouring hot coffee into
a glass that's been in the fridge. The glass shatters from the shock".
But there is no rational comparison of the two phenomena. Any explanation
by resort to "thermal stress" must provide for heat transfer
rapidly through thousands of feet of insulating material, something inconceivable
even if you ignore the deep freeze of the vacuum through which the comet
is moving, with its sunward face continually changing due to rotation.
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- Another astronomer, from University of
Western Ontario, suggested, "The most likely explanation is thermal
stress, with the icy nucleus cracking like an ice cube dropped into hot
soup". All that this "explanation" requires is a little
home experiment. The ice cube will not shatter explosively, or any way
display effects comparable to the disintegration of Schwassmann- Wachmann
3--not even if dropped into boiling water. It will melt. And no matter
what a comet is composed of, the heat transfer the "theory"
implies for a mile-wide solid object is beyond all reason.
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- In addition to citing possible "thermal
stresses", the Hubble Space Telescope website offers other possibilities
as to why comets might disintegrate so explosively--"They can also
fly apart from rapid rotation of the nucleus, or explosively pop apart
like corks from champagne bottles due to the outburst of trapped volatile
gases". But the centrifugal forces acting on comet nuclei are close
to zero. And to posit heating in the middle of a mile-wide dirty ice cube
is, again, scientifically indefensible.
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- Perhaps then, Schwassmann-Wachmann 3
"was shattered by a hit from a small interplanetary boulder?"
offered one of the astronomers quoted above.
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- "But make that a series of one-in-a-trillion
hits", mused a critic of today's comet science. "That way we
can explain the continuing fragmentation over years".
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- Comet science is indeed in trouble, and
it is particularly dismaying to see spokesmen for the Hubble site announcing
that their telescope may help to "reveal which of these breakup mechanisms
are contributing to the disintegration of 73P/Schwassmann-Wachmann 3".
Neither NASA, nor the Hubble folks in particular will find evidence for
any of the "hypotheses" offered, say the electrical theorists.
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- From an electrical viewpoint the periodic
breakup of comets is no surprise. Fragmentation and disintegration illustrate
the same dynamic forces observed in the "shocking" outbursts
of comets. Electrical outbursts and complete disintegration are merely
matters of degree in a discharging or exploding capacitor, which is exactly
what an "active comet" is in the electrical interpretation.
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- [Link: "The Explosive Demise of
Comet Linear"--http://www.thunderbolts.info/tpod/2005/arch05/ 050520linear.htm]
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- A capacitor, one of the most commonly
used devices in electrical engineering, stores electrical charge between
layers of insulating material. And that is what a comet moving through
regions of different charge will do--it will store electric charge. A
comet nucleus can be compared to the insulating material, the dielectric,
in a capacitor. As charge is exchanged from the cometâ¤s
surface to the solar "wind" (actually an electrically active
plasma), electrical energy is stored in the nucleus in the form of charge
polarization. This can easily build up intense mechanical stress in the
comet nucleus, which may be released catastrophically. And just as a capacitor
can explode when its insulation suffers rapid breakdown, a comet can do
precisely the same.
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- As suggested by electrical theorist Wallace
Thornhill, "comets break up not because they are chunks of ice 'warming'
in the Sun, and not because they are loose aggregations of smaller bodies,
but because of electrical discharge within the nucleus itself".
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- [Link: "When Comets Break Apart"--http://www.thunderbolts.info/tpod/2006/arch06/
060119comets.htm]
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- Schwassmann-Wachmann 3, first observed
in 1930 and named after its two German discoverers, has never put on a
spectacular display comparable to such "Great Comets" of the
twentieth century as Halley, Hale-Bopp, and Hyakutake. It is a short-period
comet: for electrical theorists that means a lower-voltage comet-[--and,
as a rule, less drama.
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- Schwassmann-Wachmann 3 completes an orbit
every 5.4 years. Its path takes it from just beyond the orbit of Jupiter
to inside the orbit of Earth. But it does not visit the more remote regions
of the solar system, while the spectacular "Great Comets" spend
long periods adjusting in that more negative environment of the Sun's
domain before racing sunward. What Schwassmann-Wachmann 3 does exhibit,
however, is a highly elliptical (elongated) orbit, so in electrical terms
that means more rapid transit through the Sun's electric field and more
intense stresses on the capacitor than would be the case were the comet
moving on a less eccentric path between the regions of Jupiter's and Earth's
orbits.
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- The comet is presently headed toward
perihelion, or closest approach to the Sun (within 87.3 million miles),
on June 6. Well before then, on May 12th it will pass within 7.3 million
miles of Earth. Though that is roughly 30 times the distance of the Moon
from Earth, many earthbound and space telescopes should capture images
of the comet in sufficient resolution to provide additional critical tests
of the electrical model.
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