🪐 Ancient Greek Astronomy Tools on Display These fascinating instruments come from the Greek period in Egypt and are now housed in the National Museum of Egyptian Civilization. 🔭 Among the objects are: An astrolabe, used to measure the positions of celestial bodies A sundial, used to tell time by the position of the sun Star-positioning tools to help ancient astronomers track the heavens And a beautiful sand-filled hourglass, possibly once used with water to measure precise astronomical interv