HP Clock

Monday, January 7, 2013

More Junk Box Astronomy & the Transit of Venus

I thought it would be a good idea to do my intended post about the Transit of Venus before it happens again.  Of course that won’t happen in our lifetime since the next two transits of Venus will happen in December 10–11, 2117, and in December 2125.  My inspiration for this post was based on my reading of the book by Andrea Wulf “Chasing Venus”.

The book brings to life what was the first big international scientific collaboration.  Sir Edmund Halley, knowing that he would not be alive to see the results, postulated that by accurate measurement the physical size of the solar system could be determined.  He encouraged his younger contemporaries to undertake the adventure that would take them to the far ends of the earth to make their measurements.  Here you can see what was predicted for the transit of 1761.

For us, our adventure led us to the top of the parking structure at the office where I work.  Using the same set up that I had used just a few weeks earlier to view the partial eclipse of the Sun by the Moon we waited for Venus to appear in front of the Sun.  

In this projected image both Venus and Sun spots can be easily  seen.  The large fuzzy ring in the projection is an artifact of the folded optic system used by the telescope. only one person asked why Venus did not catch fire...

One of us brought the darkest of welding goggles.  This did work, but Venus was barley visible since there was no magnification with this method.

In this Green image the goggles were simply placed over the eye piece of the telescope and the picture was taken with a phone camera.  We had to work quickly since the focused rays of the Sun on the goggles heated them to very high temperatures within a minute of exposure.