Hipparchus, who used an eclipse of the Moon to deduce the precession of the equinoxes ( here ), used a total eclipse of the Sun --probably in 129 BC--to estimate how far the Moon was. But he also derived the Moon's distance from a lunar eclipse--see here .) That eclipse was total at the Hellespont--the Dardanelles, part of the narrow strait that separates the European and Asian parts of Turkey--but only 4 / 5 of the Sun were covered in Alexandria of Egypt, further to the south. ...