An algebra-based overview of elementary and pre-telescope astronomy. Topics covered include sundials, seasons, calendars, precession, shape and rotation of Earth, Greek astronomy, the path to heliocentric theory and...

This pair of web pages, authored and curated by David P. Stern, describes early calculations of the Earth-Moon distance by Greek astronomers. Using lunar and solar eclipses, the astronomers Aristarchus and Hipparchus...

Authored by Nick Strobel, these web pages give a brief history of the imporatant figures associated with shaping Astronomical thought into what it is today. It covers the work and discoveries of the ancient Greeks,...

This web page, authored and curated by David P. Stern, describes the precession of the Earth's axis of rotation relative to the stars. It describes the discovery by the Greek astronomer Hipparchus that the position of...

This web page, created by David P. Stern, describes observations that show the earth is a sphere and the history of these observations. The round shape of the Earth may be inferred from the existence of a horizon at sea....