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Hi Jackie, I'm in Como Italy right now,
gl

On Apr 20, 9:12�am, "Jackie Ferrari"  wrote:
> 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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