[meteorite-list] Good read about the moon being captured by Earth

[Richard Kowalski]

"Science progresses one funeral at a time." -- Max Planck

--
Richard Kowalski
Full Moon Photography
IMCA #1081


--- On Sat, 12/18/10, almitt2 at localnet.com <almitt2 at localnet.com> wrote:

> From: almitt2 at localnet.com <almitt2 at localnet.com>
> Subject: Re: [meteorite-list] Good read about the moon being captured by Earth
> To: meteorite-list at meteoritecentral.com
> Date: Saturday, December 18, 2010, 10:43 PM
> Greetings,
> 
> The Earth capture theory creates a lot of problems due to
> the size of the Earth/Moon system. I believe it is
> physically impossible. It has long been discarded as a
> viable theory.
> 
> More likely an impact occured with the Earth during
> formation. At least that is the most logical idea put forth
> so far.
> 
> I guess that bad ideas are defended until the death of the
> person that generated the idea. Tektites also come to mind.
> 
> --AL Mitterling
> 
> 
> Quoting MEM <mstreman53 at yahoo.com>:
> 
> > ----- Original Message ----
> >> From: Greg Catterton
> >> Subject: [meteorite-list] Good read about the moon
> being captured by Earth
> >> about a year  old but a good read and
> something to consider. I think this
> >> theory is more  plausible also.
> >> Maybe the moon was hit and knocked towards Earth
> and was  captured.
> > 
> > Yeah...BUT.....Capture theory doesn't address the
> identical oxygen isotope
> > ratios shared by Terra and Luna. Nor our 23° axis
> tilt. Nor the migration
> > dynamics to move .88 AU in 100 million years to be in
> place for the capture.
> > According to the article, Malcuit has been working on
> this for several decades.
> > While Malcuit wasn't looking up from his desk, he may
> have missed the little
> > isotope-ratio "thingy".
> > 
> > While some rocks in Australia were dated to 4.0±.03
> billion, the claim for the
> > oldest earth rocks dated were in the range of 3.8-4.3
> billion( a one half
> > billion error margin) leaving 400-500million years for
> the surface to
> > re-congeal--which the author doesn't think is
> adequate.  The wack obviously
> > would have excavated some of the mantle but not
> necessarily the core.  I haven't
> > seen the math, so I don't know if the envelope of
> possibilities allow for some
> > deep-crust plutons to have avoided being
> disrupted.  Maybe we need to be looking
> > for plutons with giant shattercones rather than
> micrometer-sized zircon
> > crystals.  Another caveat in this "dating" is it
> isn't the rocks themselves
> > which are that old-- its the un-remelted zircons
> within them and a giant wack
> > would not necessarily have melted every last reservoir
> of zircon.  The zircons
> > in Australia were in much younger sandstone.
> > 
> > I'd like to know more about the mechanism of capture
> to convert a highly
> > elliptical orbit (which would be likely be passing
> inside the Roche radius of
> > the earth 16 times per year) into an almost circular
> one. ( I'd like to hear
> > more about the wack from the orbit from inside Mercury
> and how the Moon would
> > have retained so much silicate content which should
> have been boiled away).
> > While we know there is a small, permanent, tidal
> bulge, on the backside of the
> > moon, the moon is far far less ellipsoid then
> predicted given the perturbations
> > of the Roche limit would have exerted over part of the
> 3 billion years of
> > stabilizing--AND the moon would have to have been
> largely plastic-- if not
> > molten , for the ellipsoid to become spherical. 
> BUT the moon is missing
> > compression ridges that would have been left by the
> tectonics a solid crust
> > floating on a plastic lunar mantel. I do agree that
> the churning would have
> > heated both earth and the moon if the moon had
> survived the capture for any
> > length of time--according to this theory. And we have
> calculated the rate the
> > moon is moving away from us such that 400mybp we had
> 20 hour days. So where is
> > the orbital mechanics that got the moon so close and
> only to let it assume a
> > different orbital radius?  The mechanism should
> have been a single vector not
> > first one than another.
> > 
> > I would also like to know what these "geologically
> impossibilities" are the
> > author did not elaborate on other than his argument on
> cooling rates and the
> > inferred "earliest age" the zircons could have formed
> that we use to date the
> > oldest rocks.   This is the first I've
> heard that the" Big Wack" was estimated
> > to have occurred after the earth had formed oceans.
> > 
> > 
> > Finally, some do believe there were a dozen or more
> bodies in the very early
> > solar system that were ejected out of the solar system
> else were absorbed into a
> > body that yet remains. Calculations show that there
> are resonances and that
> > bodies have moved into orbits other than the ones they
> were formed in but IIRC
> > these were largely inward migrations(?).  What
> wacker "knocked" the moon into a
> > radical orbit and where is the wacker today?
> > 
> > 
> > Seems someone has too much of their life invested in a
> theory overcome by events
> > to accept that it is only a matter of time before the
> memorial service.  Thanks,
> > however, was a good read and I think we are open
> minded enough to weigh the
> > facts.  Now if I can just get someone to agree
> with me about cold vs hot
> > meteorites...
> > 
> > Elton
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> 
> 
> 
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