eng

### first geodetic problem <differential geometry, geodesy>

### direct geodetic problem <differential geometry

### geodesy>

problem that given a point on a surface and the direction and distance from that point to a second point along a geodesic, determines that second point

Note to entry: This "problem" defines a mapping from the vector space at a point (each vector given by a direction and a length) to points of the Figure of Earth that satisfy the problem for that direction and distance. For example, if we fix the distance "r" and take all directions, the resultant geometry is the circle centred at the original point of radius "r". This document will make heavy use of this mapping; see exponential map and the second geodetic problem.

ORIGIN: ISO/TC 211 Glossary of Terms - English (last updated: 2020-06-02)