Re: 3rd notes on Phil. Stott (fwd)
David Campbell (bivalve@isis.unc.edu)
Mon, 16 Jun 1997 13:28:21 -0400>>
>> 23. Comets (here I must take a pot shot - I'm sure he used a photo of a
>> meteor - red, bring "tail", bright background) are shortlived critters.
>> They emit massive amounts of gas/dust. Therefore there continued
>> presence argues for a young solar system.
>>
>Sorry, your pot shot is wrong, the slide showed comet Ikeye-Seki.
>
>> 24. The theory of the Oort cloud is totally unproven, along with any
>> traveling neighbor star. The orbits of comets show that they could not
>> have come from such a symmetrical source. Therefore the solar system is
>> young.
>>
>Rather, therefore the Oort explanation is not tenable, hence
>there is one less ad hoc explanation of how the solar system could be
>old. The main point here was to introduce Carl Sagan's statement:-
>"Many scientific papers are writen each year about the Oort cloud -
>its origin its properties its evolution. Yet there is not a shred of
>observational evidene for its existence." My comments were not aimed so
>much to the conclusions to be drawn for the age of the solar system,
>but on the value of "science" which is built on "not a shred of
>observational evidence."
>
I've encountered several variants of this claim from young-universe
sources. It overlooks the fact that the Kuiper {spelling?} belt is
well-documented now, and several comets have been detected out there.
Whether or not the Oort cloud exists, the trajectory of several comets
clearly shows that they have come from far away in the solar system, if not
beyond. Hyperbolic (i.e., open) "orbits" are the most obvious examples of
new arrivals in the inner solar system. Conversely, meteor showers and a
lot of the dust in space or piled on the moons and planets are remains of
old comets. This information shouldn't be hard to find-my background in
astronomy is one semester of grading astronomy homework, frequent browsing
of Sky and Telescope magazine, and the like.
David Campbell