4 June 2004

More on Venus

The Venus transit was a major theme throughout Mason & Dixon, and it is a signature trademark of Pynchon's stories. Many of his themes deal with ineffable transition periods (e.g. the parabolic arc of a rocket as it changes from ascending to descending in Gravity's Rainbow).

The reason behind early attempts at recording the transit was to calculate the distance of the Earth from the sun (the astronomical unit).

At the suggestion of Edmond Halley, the transit pair of 1761 and 1769 was used to try to determine the precise value of the astronomical unit using parallax. Numerous expeditions were made to various parts of the world in order to observe these transits; in effect this was the first international scientific collaboration.

Pynchon had Jeremiah Dixon involved in this measurement. I never researched whether Dixon actually did this or not.


I guess Dixon was involved. MSNBC has a good overview:

Astronomer Charles Mason (1730-1787) and his assistant, surveyor Jeremiah Dixon (1733-1779) originally planned to travel to far-off Sumatra (in modern Indonesia) to observe it.

But upon leaving Portsmouth, England, their ship was fired upon by a French frigate, heavily damaging the vessel and killing eleven on board. As a result, Mason decided against observing the transit, but received a harsh reprimand from the British government, who urged him to try again.

So Mason and Dixon set sail in February 1761. Two months later, they arrived at the Cape of Good Hope in South Africa. When they received word that the French had just occupied Sumatra, they decided to observe the transit from the Cape. As it turned out, it was the only successful observation made from the Southern Hemisphere. Two years later Mason and Dixon signed an agreement with the proprietors of Pennsylvania and Maryland to assist in resolving a boundary dispute between the two provinces, finally delineating what was to become famously known as the "Mason-Dixon Line" in 1766.


Here's a BBC article with a simple overview of the transit and a link to a Flash animation showing the relationship between Earth's and Venus's orbits around the Sun.

[ posted by sstrader on 4 June 2004 at 1:45:27 PM in Science & Technology ]