[meteorite-list] ELE impact cycles

From: E.P. Grondine <epgrondine_at_meteoritecentral.com>
Date: Thu, 20 Sep 2007 15:38:46 -0700 (PDT)
Message-ID: <659082.46146.qm_at_web36911.mail.mud.yahoo.com>

Hi Sterling, list, all -

Sterling, thank you for taking the time for your
thoughtful reply.

It seems to me that the possibilities also exist that
either the radioisotope decay used for geological
dating is off by a little bit, or the dating used from
red shift inference is off by a little bit. Whether
one of those two, or another mechanism is involved
define work yet to be done. Whew! - someone else's
not mine.

E.P. Grondine
Man and Impact in the Americas
 
--- "Sterling K. Webb" <sterling_k_webb at sbcglobal.net>
wrote:

> So, the possibilities are that the movement of
> the Sun above
> and below the Galactic Plane have been miscalculated
> by 20%
> (possible, but not that likely), OR that the cycle
> time varies by
> the Sun's position in the Galaxy (Galactic orbits
> are "random
> walks," not Newtonian clockwork), OR that the 26
> million year
> extinction cycle is due to something other than the
> Galaxy-Comet
> interaction, OR that the Oort Cloud is disturbed on
> a 26 million
> year cycle by something other than the "Galactic"
> effect (dark
> massive companion), OR... It's like a grand
> smorgasbord of
> hypotheses, isn't it?
>
> The timing discrepancy may be resolved in the
> future, or
> explained, but right now it makes the comet
> correlation a puzzle,
> not a solution. It may never be resolved. These are
> geological
> and cosmological processes, slow and subject to many
> kinds
> of perturbation; they may be cyclical but variable;
> we may just
> not have enough data yet. Their specific "history"
> is hard to
> derive from the geological record, which for all
> practical
> purposes means only the last 500-600 million years
> is useful.
>
> And we haven't even mentioned the 10-20 GMC's
> (Giant
> Molecular Complexes), huge dust clouds, full of new
> stars and
> with the mass of a million Suns, which circulate in
> the Galactic
> Plane. We've had to run into (and through) one of
> those monsters
> every half billion years (or less). They are a far
> greater danger than
> any (or all-of-the-above) of the hazards above.
>
> We're spoiled. We happen to be in a very safe,
> low-hazard
> region, far from the Galactic Plane, outside a
> spiral arm, distant
> from the Galactic Center, swept clean of gas and
> dust, and thinly
> populated with other stars: astronomers call it "The
> Local Bubble."
> We're not experiencing any storm of bonbardments;
> the local
> ice age is in a mild interlude --- Gee! Everything
> is just perfect!
> Like everyone who has grown up in a really nice
> neighborhood,
> we think the outside world, too, is a "nice" place,
> just like home.
> Because of this, we tend to grossly UNDER-estimate
> the hazards
> that do exist. We are basically "clueless."
>
>
> Sterling K. Webb



      ____________________________________________________________________________________
Tonight's top picks. What will you watch tonight? Preview the hottest shows on Yahoo! TV.
http://tv.yahoo.com/
Received on Thu 20 Sep 2007 06:38:46 PM PDT