Transit of Venus

How far away is the sun?

To answer this simple question took a huge amount of cooperation in what was to be the first international scientific collaboration of its kind. Nowadays international scientific projects are commonplace, but in the 18th century it took a rallying call to observe an a rare astronomical event. This event had been predicted to occur in 1761 and again in 1769 and the scientific community was determined to take advantage of this prediction to collect data for a mathematical solution to find the distance to the sun first proposed over 50 years earlier.