Re: ZetaTalk and Spaceguard UK

Bill Nelson wrote:
> In Article <[email protected]> Kevin W. Parker wrote:
>
>>> Indeed, where is the push-away law of gravity, that puts
>>> a perturbed planet BACK into its safe distance from the Sun,
>>> once it has been perturbed closer in to the Sun.  Math
>>> formulas were evolved in a mode where they were
>>> tweaked until they WORKED, and when they no longer
>>> worked, tweaked again with different factors until they
>>> worked again. Newton went up to a mountain top and
>>> came down with the Inverse Square law written on a tablet?
>
>> In the Principia, Newton actually tries out the effect of
>> several various laws on planetary orbits, such as an inverse
>> cube law (which would have the planets spiraling slowly
>> inward). The inverse square law is the one that matches
>> Kepler's conclusions as to the planets' elliptical orbits.
>
> This is not at all surprising, as circumference increases
> directly with the square of the radius.  You can easily
> demonstrate that light decreases in direct proportion to
> the inverse square of the distance. If gravitation behaves
> at all like light, it should do so as well.

So, Newton was dissatisfied with his conclusions?  Felt there was
something still out there?  Didn't feel his work was completely done?
Good for him!  He didn't slam the books closed and pronounce that
mankind now knew all, and this was the end of quests and problem
resolution, forever?  A true scientist is always dealing with the facts
and seeking new information.

So, any theories on why planets perturb BACK into their orbits, after
having been perturbed in toward the Sun?  No one has questioned this?
Other than David Tholen's explanation that the Sun moves and Pluto does
not notice, that is ...

David Tholen wrote:
>>> But they do perturb "closer into the Sun".
>>> Consider the osculating semimajor axis for Pluto
>>> as of  epoch  2444800.5 = 1981 July 15
>>>    39.9165 AU
>>> and as of epoch 2451800.5 = 2000 September 13
>>>    39.2353 AU
>>> From DE403.
>
>> Then why not STAY closer in to the Sun, after having
>> arrived there? ... perturbing Pluto to orbit closer to the
>> Sun by their combined gravity pull, then what is it that
>> pulls Pluto BACK AWAY from the Sun?
>
> Perturbations can work both ways.  Six years later, Jupiter
> will be on the other side of the Sun, causing the barycenter
> to shift, thus the heliocentric osculating orbit for Pluto
> will now be different. It's called indirect perturbations.

Pluto is the OUTERMOST Planet (for those of you denying Planet X
existence).  How can Jupiter, anywhere, do a push-away from the Sun to
Pluto!  You're saying the Sun moves away from Pluto, and Pluto just
stays where it is, not noticing?  Are we being silly here or what?