Wednesday 13 June 2012

Venus Transit

    This post is a bit late, but as the skies were completely clouded over here last week during the second (and last) transit of Venus this century and we were unable to "observe" it, I was prompted to dig out the photos and revisit our observation at Ipolera in 2004.

    The sun is always shining in Central Australia, so one day after school I set up an observation post.




    The equipment consisted of a stack of books supporting binoculars with the big ends facing the sun.  The binoculars projected two images of the sun onto a sheet of white paper, emulating a pinhole camera.




Because the sun was also shining on the sheet of paper, I made some shade with my hand to provide sufficient darkness for the binocular images to be seen by the camera in my other hand.




    The result was this image, with Venus clearly visible on the sun's surface at about 7 o'clock.  The thrill of this observation, as opposed to internet or TV images, was the fact of "being there" to experience the immediacy of it.

    We heard a program on Radio National about the history of Venus transit observation.  The first time humans saw it and knew what they were looking at was in 1639, after the advent of telescopes.  Jeremiah Horrocks, a teenager at the time, realised that Keppler had his maths wrong, and with his (Horrocks') corrections was able to predict that the 1639 event would indeed be observable rather than below the horizon as Keppler thought.  Of course, Horrocks successfully observed it, at the tender age of 21.  (He died aged 23).  Amazing!

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