Seleucus of Seleucia was an ancient astronomer who defended heliocentrism, arguing that Earth orbits the Sun and rotates on ...

Dallas shows an orrery – a mechanical model of the solar system. Before the 17th century most people believed in a geocentric model of the solar system. Dallas explains the geocentric model and ...

In the chaotic aftermath of Mongol expansion in the mid-13th century which had left the Abbasid capital of Baghdad in ruin, a new centre of learning soon came to the forefront. Ironically it was the ...