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    Re: Lunar distance this Sunday
    From: Alexandre Eremenko
    Date: 2017 Apr 14, 17:08 +0000

    Frank,
    I would say that the lunar distance on an Easter can be anything, with equal probability.
    
    Accroding to Wikipedia, the date of Easter is not determined anymore by strict
    astronomical rules.
    
    The original definition was the "first Sundday after the first full moon after the spring equinox".
    
    But the ecclesiastical rules (as exlained in Wikipedia) the equinox must be counted on 21 of March,
    and "full moon" is the 14th day after the new moon first visibility.
    
    However this difference does not matter for my answer.
    
    The moon phases wander over the solar year, so on any day of the solar year, say March 21
    all moon phases are equally probable (in the long run). Because the periods of 
    the Sun and Moon are "incommensurable"
    for all practical purposes.
    
    From this follows that all distances are equally probable, if you average over a very long period.
    I suppose that the 2000 years or so is a sufficiently long period.
    
    Alex. 
    
      
    ________________________________________
    From: NavList@fer3.com [NavList@fer3.com] on behalf of Frank Reed [NoReply_FrankReed@fer3.com]
    Sent: Friday, April 14, 2017 12:28 PM
    To: eremenko---.edu
    Subject: [NavList] Lunar distance this Sunday
    
    This Sunday, April 16, at Greenwich noon, the Moon will be about 122� from the 
    Sun. This got me thinking... what is the average lunar distance (elongation 
    of the Moon from Sun) on Easter? The image below will explain why this is on 
    my mind.
    
    Frank Reed
    
    
    Attached File:
    [http://fer3.com/arc/imgx/sundials.jpg.thumb.jpg]
    [http://fer3.com/arc/images/dl-icon.png]
    
    
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