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    Re: Lewis and Clark lunars: more 1803 Almanac data
    From: Fred Hebard
    Date: 2004 Apr 19, 11:54 -0400

    The date being off by one day also could apply to looking for the
    "real" star from which the measure was made.  Their data seem to be
    adequate to within a minute in other shots, so a time error in
    combination with measuring to the wrong star might get a reasonable
    answer.  Usually, in my case, I make the date blunder when 00:00 hours
    has already passed in Greenwich but not yet in the U.S., although
    usually in looking things up in the almanac.  Another common blunder is
    to use local zone time as the entering argument into the almanac rather
    than Greenwich time.
    Now I'm not saying I make these two blunders all the time!, but they
    are ones for which I have to watch.
    On Apr 19, 2004, at 12:06 AM, Frank Reed wrote:
    > Fred H wrote:
    >  "Have you all looked to see whether the date is off by one day? "
    >  Yes, I checked into the possibility that there was some time offset
    > (this might arise during the transcription of observing notes, for
    > example). So I checked for other times during the night when the
    > observations might have made sense. Suffice to say, it doesn't work.
    > An error of whole day would be much too large if you think about it.
    > This error would yield lunars out of line by some 13.5 degrees.
    >  Frank E. Reed
    >  [ ] Mystic, Connecticut
    >  [X] Chicago, Illinois

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