The Leiden Sphaera — the dynamic model of the solar system pictured above — was built around 1670 by Dutch clockmaker Steven Tracy. The impressive cosmic model measures 1.5 meters across, and is ...

The heliocentric theory is the idea that the Sun is at the centre of the solar system and that everything else – planets, asteroids, comets and the rest – revolves around it. Prior to heliocentrism, ...

Islamic scholars significantly advanced astronomy between 800 and 1300 AD. They made precise astronomical calculations using advanced math. Their work included building observatories and inventing new ...