Local Cartesian System and Earth`s curvature
Hi lyoyha,
it is a Cartesian system defined by the principal point P0, cf. Wikipedia: From ECEF to ENU.
![[image]](https://software.applied-geodesy.org/wiki/_media/least-squares-adjustment/jag3d_local_ellipsoidal_earth_model.png)
P0 is the only point that is orthogonal to both, the local system as well as the Earth surface.
regards
Micha
![[image]](https://software.applied-geodesy.org/forum/images/uploaded/ingenieurvermessung26.png)