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    Re: Lunars for dummies like me
    From: Jan Kalivoda
    Date: 2004 Sep 25, 15:28 +0200

    Frank Reed wrote:
    Let's consider two cases:
    1) You have no timepiece, not even an ordinary watch. In a case like this,
    you would shoot your lunar and your time sight simultaneously. That is, the
    altitude of the Sun is used to clear the lunar *and* to generate Local Apparent
    Time. This requires lunars where the Sun is well away from the meridian. And
    you're basically limited to using the Sun, but that was by far the prefered
    "other body" for lunars in any case.
    Yes, but not the only option. During the twilight, you can e.g. take three 
    altitudes of the Moon and Regulus and three distances between those two 
    bodies without even marking the time. Average both sets of altitudes and the 
    set of the distances. You then have the distance and altitudes for the same 
    moment. Now from the cleared distance you have GAT and from the altitude of 
    the Regulus (if not being too near to the meridian) you will find LST (using 
    the DR latitude); change it to LAT and gain the longitude from LAT - GAT. You 
    don't need any clock, you can limit yourself to the sandglass for ringing the 
    bell and cooking eggs.
    I only repeat the procedure from Thompson's tables (1828).
    Jan Kalivoda

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