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    Re: Best ways to regain date.
    From: Peter Hakel
    Date: 2015 Nov 12, 19:57 +0000
    How about using the Moon’s phase? If Mark 1 eyeball is not sufficient then perhaps by using the sextant to measure the angular size of its crescent and correlate that with the percent illumination published in the almanac for each day (might have to build a table or a plot for that first).


    Peter Hakel


    From: Mark Coady <NoReply_MarkCoady@fer3.com>
    To: pmh099---.com
    Sent: Wednesday, November 11, 2015 8:01 PM
    Subject: [NavList] Best ways to regain date.

    Lets postulate i'm fighting a storm and horrid weather for days....lose all track of time..and finally collapse into sleep under bare poles and sea anchor.  When I try to come back to life, I am not even sure what day of the week it is. When you get really tired you just start forgetting to jot things down like it got light and dark twice....
    My first thought would be moon:
    Assuming my chronometer works, using my pelorus, I take a bearing and compare it to the correct azimuth from the NA.
    Lunar distance with another body also comes to mind as another sure fire way. 
    Sun...?  Azimuth at rise or set?  My problem here is accuracy and my tale of woe to get into this mess implies my dead reckoning and thus latitude is possibly faulty by many miles. Once latitude is not perfect, then I'm in a muddle on the sights with high accuracy demand.
    What if it is new moon? so not available a few days....
    Besides the moon,  with dead reckoning uncertain..can we find date?
    I do suppose that star declinations being very slow to change let me restablish latitude without date based on altitudes. Once I fix lat, then then more things might open up. Stars rise and set roughly four minutes earlier each day.  This might be good enough.
    Any general thoughts.  In this day and age I relaize loss of date is improbable. 
    but.....


       
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