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    Re: Grenadine Lunar Distances
    From: Fred Hebard
    Date: 2003 Feb 4, 17:53 -0500

    This is my second attempt to post Arthur's message.  I hope Herbert
    will care to respond to Arthur; I would if I were capable.  But I
    will take this opportunity to ask a question.
    
    I have been computing the comparing distance between the moon and an
    object (the one _not_ corrected for parallax and refraction), and
    that has been varying.  For instance, the moon and Jupiter were
    separating at 35.3' per hour between 2:00 and 3:00 GMT on 12/27/02
    while the sun and moon were separating at 27.0' per hour between
    20:00 and 21:00 GMT on 1/11/03.  Not all this can be attributed to
    the hourly movement of the sun; is all the rest from their not moving
    in the same direction or are there additional factors?
    
    Fred
    
    
    >Herbert, Fred,
    >Here is the second email that wouldn't post to the list.
    >Arthur
    >===============
    >
    >Herbert,
    >
    >Once again, confusion leads to greater understanding. I had not
    >considered this disaggregated view of the moon's motion relative to the
    >sun. Am I correct in thinking of the change in distance as a vector
    >resulting from difference between the vectors of their individual motion
    >against the celestial sphere? I hope I am not opening a can of worms
    >here.  I had been focused on the single dimension of the moon pulling
    >away from or closing with the moon, which for practical purposes is
    >fine, but I am interested in understanding the components. Thanks.
    >
    >Arthur
    >
    >
    >----Original Message Follows----
    >From: Herbert Prinz 
    >Reply-To: Navigation Mailing List 
    >To: NAVIGATION-L@LISTSERV.WEBKAHUNA.COM
    >Subject: Re: Grenadine Lunar Distances
    >Date: Mon, 3 Feb 2003 15:25:40 +0000
    >
    >Arthur,
    >
    >Oops, I confused two output parameters from my program. The value of 24'
    >/ h
    >which I have quoted is the topocentric apparent motion of the moon
    >w.r.t.
    >the celestial sphere, i.e corrected for parallax and refraction. It is
    >irrelevant in this context. The change in distance to the sun is indeed
    >21'.
    >The two values differ in two respects: 1. The moon is not moving exactly
    >into the direction of the sun. 2. The sun itself moves east at a speed
    >of
    >2.5' / h. Sorry for the confusion.
    >
    >Herbert Prinz
    >
    >
    >
    >Arthur Pearson wrote:
    >
    >  > * Regarding hourly rate of change in distance: for the Jan. 10 lunar
    >I
    >  > got 21', Herbert 24', Fred 27'. I still get 21'/hour, but this is for
    >  > the apparent distance after correction for parallax and refraction.
    >For
    >  > the geocentric distance, I get an hourly change of 28' for the Jan. 7
    >  > lunar, 27' for the Jan. 10 lunar. This seems to explain the
    >difference
    >  > with Fred, still not sure with Herbert.
    >
    >
    >Arthur Pearson
    >arthurpearson@hotmail.com
    >
    >
    >Arthur Pearson
    >arthurpearson@hotmail.com
    >
    >_________________________________________________________________
    >Tired of spam? Get advanced junk mail protection with MSN 8.
    >http://join.msn.com/?page=features/junkmail
    
    
    --
    --------------------------------------------------------------------------
    Frederick V. Hebard, PhD                      Email: mailto:Fred@acf.org
    Staff Pathologist, Meadowview Research Farms  Web: http://www.acf.org
    American Chestnut Foundation                  Phone: (276) 944-4631
    14005 Glenbrook Ave.                          Fax: (276) 944-0934
    Meadowview, VA 24361
    
    
    

       
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