Hello,
I am in the attempting to understand the details behind the ellipsoid and geoid concepts as they relate to datums. I understand some of the basic concepts of the ellipsoid and geoid, and my research suggests that the ellipsoid is defined with an anchored point based on the International Terrestrial Reference Frame (ITRF). I have to assume this refers to an origin anchor point (earth center) but have to ask if this understanding is correct and is it one anchor point or several that are used?