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My sources were:

"James A. Van Allen, Basic principles of celestial
navigation, American Journal of Physics -- November
2004 -- Volume 72, Issue 11, pp. 1418-1424."

and


"Michael Dorl wrote-

| Back in 1999, I sat down and worked out the spherical trig for this
| problem.  It may be found at
|
| http://ns.doit.wisc.edu/~mdorl/Sight%20Reduction%20write%20up.doc
|
| I am pretty sure it handles all the quadrant problems  I did not
consider
| problems at angles when the trig functions misbehave."



On Jun 17, 1:22�am, Geoffrey Kolbe 
wrote:
> Very nice. I hope these aliens gave you a rubber dinghy so you can paddle
> to Pearl Harbour :-)
>
> To save reverse engineering the spread sheet, what were the analytical methods?
>
> Geoffrey Kolbe
>
> At 01:29 17/06/2008, you wrote:
>
>
>
> >You really know quite a lot. �If it's 0600GMT (approx their morning
> >twilight) and it's your evening twilight, you must be approx 12 hours
> >different, or the other side of the world. �Plot the Ground Points of the
> >three stars as on the attached. �For latitudes up to the give 30 deg N,
> >the distortions aren't outrageous. �Draw the Zenith Distance Circles of
> >Position. �Spica is about the right length since it's North-South. �Since
> >Vega-Pollux intersect somewhere not too far from north of Spica and are
> >mostly East-West, scale the lenghts on this plot by 1/cos(Lat). �So AP
> >could be somewhere near 25N, 157W.
>
> >But no AP is needed it you're willing to do some math. �The attached
> >spread sheet shows two analytic methods (which, luckily give the same
> >answers). �It can be seen, the 3 intersection points are: �23-18.4N
> >157-17.5W, 23-18.4N 157-17.5W, and 23-18.3N 157-17.6W- Hide quoted text -
>
> - Show quoted text -
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