Four amazing astronomical discoveries from ancient Greece

The Histories by Herodotus (484BC to 425BC) offers a remarkable window into the world as it was known to the ancient Greeks in the mid-fifth century BC. Almost as interesting as what they knew, however, is what they did not know. This sets the baseline for the remarkable advances in their understanding over the next few centuries – simply relying on what they could observe with their own eyes.

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Tau.Neutrino said:

Four amazing astronomical discoveries from ancient Greece

The Histories by Herodotus (484BC to 425BC) offers a remarkable window into the world as it was known to the ancient Greeks in the mid-fifth century BC. Almost as interesting as what they knew, however, is what they did not know. This sets the baseline for the remarkable advances in their understanding over the next few centuries – simply relying on what they could observe with their own eyes.

more…

> One of Aristarchus’ books that did survive is about the sizes and distances of the Sun and Moon.

Yes. He got the Moon right and the Sun too close. It’s hard enough to calculate the distance to the Moon. Try it some time.

He did however conclude that the Sun is bigger than the Earth.

> The Earth’s circumference.

Different ancient Greeks got different circumferences for the Earth. Two got it almost spot on. It’s annoying that Ptolemy later chose the wrong one, and ended up with a diameter for the Earth too small.

Looking further down the web page, this article is interesting:

Why does Venus’ atmosphere spin much faster than the planet?