9 ms·
Unless the sun was VERY close, the actual distance doesn't matter. What matters is that the sun (or a star, or whatever you use as a reference) is so far away t
by drpixie 3y ago
Unless the sun was VERY close, the actual distance doesn't matter. What matters is that the sun (or a star, or whatever you use as a reference) is so far away that there is no practical difference between "far away" and "even further".
For practical purposes, we treat the sun as being an infinite distance away, and the error caused by it being ONLY 93,000,000 miles away is much smaller than Eratosthenes could measure :)
It's similar to drawing perspectives, you draw perspective lines to join at the distant horizon. You don't care how far to the distance horizon.
(Those ancient Greeks had amazing understanding of geometry. Much better than most of us.)
- alehlopeh 3y agoGood answer but weirdly judgy last sentence. More like, a handful of ancient Greeks had a better understanding of geometry than most of us, just like a handful of us has a better understanding of geometry than most of us. And of course, a handful of us has a better understanding of geometry than most ancient Greeks.
- drpixie 3y agoDidn't mean to come across judgy :( Apparently the ancient Greeks didn't have much, if anything, in the way of symbolic algebra or calculus - what we mostly think of as "maths". Instead their normal tool for mathematical logic was geometry. An educated Greek would have used geometry much like we use algebra. For most of us, given a non-maths problem (eg physics, chemistry, almost anything in real life...) the first thing we do is express it as an algebra problem, and solve that. The ancient Greeks used geometry in a similar way.