how should i say this?
there once was a TV show called "connections". in one episode, they talked about someone who observed shadows.
in one place on earth, on a certain date and time, the sun was PERFECTLY straight up, so tall columns had NO shadow at all. but at the exact same time, in the place where he lived, the columns had a LONG shadow.
so he measured the distance between, did some calculations, and concluded...that earth if round! he even he even figured out it's size from those figures!
Modern RErs say his size figures were about 5% off; quite understandable, given the primitive measureing instruments of that time.
but FErs say that he was wrong, that the sun is actually much smaller and closer, thus producing "misleading" results.
but if the sun was THAT close, someone on the ground and someone on an airplane directly overhead would see the sun at noticably different angles!
FACT: they do NOT see different angles!