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Re: Systematic Error (LOPs revisited)
From: Bill Noyce
Date: 2003 May 28, 11:23 -0400
From: Bill Noyce
Date: 2003 May 28, 11:23 -0400
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.
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
