On Feb 27, 1:36*pm, "Painius" wrote:
"oldcoot" wrote in message...

...

From Painius, replying to 'BG':

I was just asking you where you had
heard or read that our Solar system
experiences a wobbling cycle that has a
period of 105 to 110 thousand years.

I think he's referrin' to the presumed "oscillation" of the solar
system's pathway above and below the galactic plane, *theorized also to
trigger mass extinctions on a regular basis.

Possibly, but that's only supposed to happen 2.7 times per
galactic year (~225 - 250 million Earth years)...

*http://en.wikipedia.org/wiki/Sun#Loc...hin_the_galaxy

If one divides 225 by 2.7, it means that the Sun and Solar
system oscillate above and below the galactic plane with
a period of about 83.3 million years--much longer than
Brad's period of 105 to 110 thousand years.

So i think he's referring to the minor ice ages that have
taken place during the Pleistocene period. *Apparently, he
believes that close passages of Sol and Sirius may have
caused these ice ages and deposited such things as the
Moon and Venus in our Solar system. *Since he does not
appear to understand orbital dynamics any better than i
do, he doesn't accept the explanation given by a poster to
sci.astro several weeks ago, to wit...

The blue-shifted radial velocity between Sol and Sirius can
be plugged into an orbital-dynamics formula, which shows
without a doubt that Sirius cannot possibly be in any kind
of orbital relationship with the Sun.

Being a lover of math, i tend to go with this reality. YMMV

I tend to favor whatever a good supercomputer simulation of stellar
orbital interactions might suggest. Otherwise the 11,711 year old
termination of the last ice age this planet Earth w/Selene will ever
see, is objectively good to go. Since you have nothing better to
offer, why should we ignore all other science, simply because it
doesn't help your side of this argument?

~ BG