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Transit of Venus, 2012

This is the 2004 one. From Toronto, at 1830h EDT, it was about 180 degrees away in the "12:30" position.

Just saw it, thanks to my sextant, as did my wife and son with theirs.

Will check it out again in an hour or so (well, before sunset!)

It makes me feel connected to the scientists, instrument makers and mariners of the last three hundred years who realized how observing the transit could not only give them a fairly accurate idea of the distance from the Earth to the Sun, but refined the measurement of longitude, confirmed the size of the Earth, and drove innovation in mechanical design that gave us the chronometer, itself a key part of the Industrial Revolution.

Captain Cook's voyage in 1766 to Tahiti was, in addition to being the 18th century equivalent of interstellar travel, was primarily to observe a prior transit of Venus about as far from London as possible in order to use the miracle of parallax to determine longitude and the size of the Earth. There was more to it than that, but the historical importance of this relatively rare celestial event is well understood, particularly by sailors still keen on celestial navigation.

It also makes me think of the Police song that goes "there's a little black spot on the sun today...", but that's kinda trivial by comparison...

1 comment:

Robert Benner said...

Cool photo. We missed it totally being on the wrong side of the planet and all. :)