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>Peter Fogg:
>> >Lets start with those 2 intersecting LOPs. If there is a systematic error
>> >then it will be either towards the direction of the 2 azimuths or away.
>
>George Huxtable:
>> Sorry, but I'm lost already. Presumably Peter is discussing here LOPs from
>> compass bearings of landmarks.

Then Bill Noyce pointed out-
>
>I think the later discussion makes clear that Peter is discussing
>LOP's from celestial observations.  In that case, if you draw
>an arrow from each LOP, toward the body observed, then one "quadrant"
>has both arrows pointing to it, one has both arrows pointing away,
>and two "quadrants" have a mismatch.  If the errors in the two
>observations have the same sign, then the true position must be
>in one of the two matching quadrants; if the errors are equal,
>the true position must be on the angle bisector that passes through
>these two quadrants.
>
>Of course, in the two-observation case, there's no information to
>estimate whether systematic errors are likely.
>
>        -- Bill

======================

Thank you, Bill. Looking back, I think Peter expressed his meaning here
clearly enough, but I was being particularly dim. Sorry about that.

George.

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