4 ms·
Certainly an interesting concept -- use simultaneous measurements to find the size of the moon. Yet I can't help but wonder from a history of science point of
by metacritic12 5y ago
Certainly an interesting concept -- use simultaneous measurements to find the size of the moon.
Yet I can't help but wonder from a history of science point of view, how much the above exercise is "presuming the conclusion". Organizing an international star party to see where the moon is at the same time requires knowing what the concept of same time on very different places on earth. But historically, the concept of same time was heavily dependent on astronomical measurements -- both astronomical knowledge and advanced instruments. Now if you start using modern techs like GPS to figure out what the concept of same time is, you're already relying on satellites and can probably use that tech to make a direct measurement of the size of the moon.
- mannykannot 5y agoYou do not need accurate time measurements for this method; the question to be answered by each observer is "was the given star occulted on the night in question?", and the ancients could track time to the precision of a day (as we are concerned with at most a hemisphere, there's no problems with date lines.) It does depend on accurate surveying over distances exceeding the diameter of the moon, and a good deal of communication, which I suspect is enough of a problem to answer the author's question of why it was not done, as far as we know. The method is not, however, begging the question.
- Smaug123 5y agoOnce you've got a reliable portable clock, you can synchronise lots of them in the same place and then move them. Harrison had done this by 1750 (with clocks that supposedly drifted by only a few seconds per day, even after sea travel).