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I've got good results for the moon and sun in a bucket of water on calm days
. I once tried a star and managed its reflection ok using the method Gary
mentions. This was in Italy up in the mountains so no light pollution but I
do recall the reflection was still very faint and the results not too good.

Jackie.


----- Original Message -----
From: "Gary LaPook" 
To: 
Sent: Monday, April 20, 2009 2:44 AM
Subject: [NavList 7993] Re: Artificial horizon question


>
> Mercury has traditionally been used for an artificial horizon (see Lewis
> & Clark) and it is easy to shoot stars using Mercury. It is rather hard
> to come by these days and is not cheap and some worry about its safety
> (I'm not one of them if used with care.)
>
> The second part of your question, compute in advance the approximate
> altitude of the star, double it and set your sextant to this value and
> then look for the star in the reflecting pool. The navigational stars
> are well separated and are bright so there should be no trouble in
> getting the right star.
>
> gl
>
> P H wrote:
>> Dear NavList Members,
>>
>> Since the nearest ocean is hundreds of miles away from where I live, I
>> must use an artificial horizon in order to work with my sextant.  A
>> pan filled with water works fine enough for me for observations of the
>> moon at night and the sun.  Now these days both the sun and the moon
>> are simultaneously visible during the day, which would allow for a fix
>> on one's position - if the altitudes of both bodies can be measured.
>> As you probably can guess, with all the glare I was unable to observe
>> the reflection of the moon... so here is my question: are there any
>> tricks that would allow one to construct a usable artificial horizon
>> for the daytime observation of the moon?  And to take it one notch
>> further, how about an artificial horizon for the stars and planets (at
>> night, of course)?  Are there any systematic methods to ensure that
>> the star reflected on the surface is indeed the one I intend to observe?
>>
>> Many thanks.
>>
>>
>> Peter Hakel
>>
>>
>>
>> >
>
>
> >
>


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