The Perfect Beauty of Venus

Venus revolves around the sun 13 times in almost exactly the same time it takes the Earth to revolve around the sun 8 times. In other words, 13 Venus years equals 8 Earth years.    

If you connect the positions of the Earth to the positions of Venus every two weeks or so, you get the “string art” pattern shown here. In his book A Little Book of Coincidence, John Martineau calls it “the perfect beauty of Venus.”  

If, instead, you put the Earth at the center of the solar system and plot the path of Venus relative to Earth for 8 years, then you get the second pattern shown to the right.

Venus's orbit is also inclined slightly to that of the Earth, so when it comes between us and the sun (5 times every 8 years), it usually passes just to the north or south of the sun. However, because the pattern described above is not quite perfect, the situation slowly but surely changes over time. As a result, Venus comes directly between us and the the sun every 105 years, and again 8 years later.  It last happened in 2004, will happen again tomorrow (June 5, 2012, starting at about 5:00 PM CDT), and then won't happen again until 2017.

Below is a photograph of Venus I took a few weeks ago.  Since then it has become a thinner and thinner crescent. Tomorrow it will be like a "new moon," not nearly big enough to eclipse the sun, but big enough to appear as a prominent black dot on the sun's surface. 

And here's a photograph of the transit. (Click to enlarge.)