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    Re: Moon Horizon
    From: Peter Fogg
    Date: 2009 May 11, 08:19 +1000
    Thomas, this is a practical problem; that of identifying the false, brighter horizon between the observer and the true horizon, and then seeing the true horizon beyond it clearly enough for use.
    If this can be achieved then moon sights throughout the night become possible, just as the sun can be used throughout the day (other factors permitting, in both cases).
    Many people have less success using the moon than other bodies, and this false horizon effect could be one reason. 
    I am not aware of any mathematical procedure, similar to a dip calculation, that would allow the false horizon to be used, with some adjustment.

    On Mon, May 11, 2009 at 7:20 AM, Thomas Kleemann <Rule_No.1@web.de> wrote:

    Hello all,

    since the discussions revolve around some practical issues in taking
    sights lately, I want to bring in an puzzlement of my own:

    In several works on celnav the authors had stated the bright reflection
    of the moon on oceans surface would obscure the visible horizon at night
    and create a line below it, called moon horizon (at least by some of them).

    If I understand the arguments correctly, it must be some kind of effect
    similar to the problems of dip and light distance?

    I thought about a function of altitude and height of eye to correct for
    that "shortness of dip"...

    Has anyone tried that successfully?

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