On the Provability of Heliocentrism. I. Ole Roemer and the Finite Speed of Light

This paper describes observational support of heliocentrism during the late Renaissance. Initiated by Galileo's clues from telescopic sightings, the first indirect quantitative support for the heliocentric doctrine resulted from accurate eclipse timings of the , made possible by breakthroughs in technology (telescope optics and the pendulum clock) and driven by the quest for longitude at sea and on land. The resulting discovery of Olaus Roemer that the velocity of light is finite, is an indirect argument supporting heliocentrism.