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 ...

Ptolemy’s model and many earlier ideas of the Solar System had the Earth at the centre of it. As observations of the motions of the planets became more detailed, the descriptions of the Solar ...

In 1508, Nicolaus Copernicus developed a celestial model of a heliocentric planetary system that transformed the way we view the universe. This bold theory, contrary to the geocentric ...