2010/5/14 Iván Sánchez Ortega <[email protected]>: >> Any ideas? I don't think that the government data is misaligned like >> that. > > You're wrong: it is. It all comes down to which reference system you > use. Unfortunately, you'll need two years of geodetics classes in a > university to have a full understanding of the issue.
Maybe a full understanding, but the basic understanding is this, originally governments used the centre of the earth as the basis, although not always some mines in Australia used the direction of the vein of ore as north/south even if it ran east/west. Since the advent of satellites spinning round the globe, and more specifically the GPS cluster of satellites, they now use the centre of the mass of the earth. _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk
