On 13 Feb, 00:21, "John Rowland"
wrote:
If only three satellites are visible, the locus of possible locations is a
straight line in space which intersects the earth's surface at two points.
Knowing which satellites are visible enables you to eliminate one of these
points, but it doesn't give you the height.

Unless the line is vertical you need to know (or guess, I suppose) the
altitude to provide an accurate lat/long.

U

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