SETI again

On Jul 29, 2006, at 1:53 AM, Robert wrote:

> its possible or its also possible that im misremembering the exact
> nature of that part of the article. perhaps it was somewhat closer
> than the oort cloud.

Articles are notorious for hyping up their stories. The old line is
"if it bleeds, it leads." As much as I love them, the Discovery
Channel and the History Channel ought to rename themselves "The
Controversy Channels" cause that's the angle they always try to play
up. Somebody is always overturning everything we thought we always
knew about everything.

A lot of people define the Oort cloud as beginning immediately after
the Kuiper belt. Observations of objects drop off VERY sharply at 50
AU's suggesting a definite end to the Kuiper belt proper. Also, about
100 AU's is the heliopause and termination shock where the sun's
whirlpool basically ends. This Heliopause would tend to push most
objects either in or out, not a lot would just hang out right there.

All of the planets, asteroids, and Kuiper belt are the material that
got sucked to the bottom of the sun's whirlpool. The Oort cloud are
the objects that are surrounding it.

Try taking a bathtub full of water and a thin layer of bubbles on
top. Create two whirlpools with your hands a short distance apart.
The whirlpool itself will seem pretty clear (unless you have too many
bubbles, like Epsilon Eridani) because most of the bubbles are sucked
down. Halfway between your two whirlpools, if they're spaced right,
you'll see the bubbles concentrate into a kind of stream or current
with very complex, bizarre motion. Now try making 400 billion
whirlpools and you get a galaxy.

The funnel, or whirlpool is the Solar system, all the planets and
Kuiper Belt. Where the whirlpool gives way to the flat water is the
heliopause, and the slightly concentrated current of bubbles halfway
in between the two whirlpools is (possibly) the main part of the Oort
cloud.

Note that if your whirlpools are too close together, there are no
bubbles in between, like in a binary star system or cluster (where
most stars are). Also, if the whirlpools are too far apart, there are
bubbles, but they don't concentrate into a stream or current..

Hopefully there are enough objects in the heliopause to allow
diffusion settlement. There are some great new telescopes in the
works that will soon give us much better answers.

Of course bathtub experiments may not apply directly to cosmic
questions, but the whirlpool seems to be a basic theme in physics.

All this talk about settling beyond the solar system is getting me
excited! Where do I get my ticket?

doug