(CdM) Not surprised it's snowy up Mount Buller. An assumption, of course, because you have quite unforgivably omitted the ρ-coordinate, which I take to be 6378137 + 1805 m. Greetings, anyway, from 51.32; -0.06, 6378306 m.

So "on the surface of the earth" is not the default, then. :-)

(CdM) Yeah, OK. Equally, I have committed the unpardonable sin of assuming the earth's radius is constant at all latitudes, which is not true. The polar radius is 21.4 km less than the equatorial radius. It's uphill to the equator.