
NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Th. Jefferson: stop wasting time on longitude
From: Alexandre Eremenko
Date: 2006 May 6, 19:40 -0500
Herbert,
> Why was this expedition not equipped with
> suitable telescopes?
The telescope had to be quite large and heavy, including the
tripod. I suppose it is also very fragile.
> Since the U.S. did not have an
> observatory of their own, Jefferson would have had to depend on
> cooperation in Europe.
Why an observatory in the US was needed?
The eclipse times of the satellites were published by European
observatories.
>Maybe he felt that the moon
>ephemeris in the N.A.
> was sufficiently reliable to stand on its own, at least more so than
> that of the Galilean satellites.
Did not those Europeans that used the method successfully use the
same Almanac?
> But now that I read this letter, I see a second explanation.
Sounds more plausible than the first one.
But it could also be that the difficulty of
transportation of a large telescope in such
expedition was the reason.
Alex.
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From: Alexandre Eremenko
Date: 2006 May 6, 19:40 -0500
Herbert,
> Why was this expedition not equipped with
> suitable telescopes?
The telescope had to be quite large and heavy, including the
tripod. I suppose it is also very fragile.
> Since the U.S. did not have an
> observatory of their own, Jefferson would have had to depend on
> cooperation in Europe.
Why an observatory in the US was needed?
The eclipse times of the satellites were published by European
observatories.
>Maybe he felt that the moon
>ephemeris in the N.A.
> was sufficiently reliable to stand on its own, at least more so than
> that of the Galilean satellites.
Did not those Europeans that used the method successfully use the
same Almanac?
> But now that I read this letter, I see a second explanation.
Sounds more plausible than the first one.
But it could also be that the difficulty of
transportation of a large telescope in such
expedition was the reason.
Alex.
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to NavList@fer3.com
To unsubscribe, send email to NavList-unsubscribe@fer3.com
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