Today the planet Venus makes a rare transit across the face of the sun. During the eighteenth century, the astronomical alignment took place twice, in 1761 and 1769, drawing observations from scientific teams all over the world, including North America. Astronomers at that time were able to produce the first truly accurate measurements of the distance between the Earth and the sun, vastly expanding the known universe and kindling the human imagination with an understanding of Deep Space.
The Declaration of Independence, a short time later, would receive its first public reading from atop a tower constructed in Philadelphia to view the transit. The American Philosophical Society, the scientific body Benjamin Franklin founded, which built the tower and organized the astronomical viewing under the leadership of David Rittenhouse (who constructed the telescope, quadrant, pendulum clock and other precision instruments necessary to do the siting) is located just next door to Independence Hall. The new cosmology went hand in hand with the new political paradigm, no longer based up the heavenly mandate of a hereditary king, but upon the equal access of all to the heavenly realms and their motions.
The Royal Astronomer of England, upon receiving a report of the American measurements, wrote that “the first approximately accurate results in the measurements of the spheres given to the world [was made] not by the schooled and salaried astronomers who watched from the magnificent observatories of Europe, but by unaided amateurs and devotees to science in the youthful province of Pennsylvania.”
What else might come out of these colonies, where men by their own wits and abilities could vie with the lords of the Old World? Today you can watch the transit online or with protective filters—your last opportunity to see what America’s Founders saw and wonder at an event that won’t be repeated for 105 years.