This week is the height of the Geminid meteor shower, which is one of the highlights of the night sky this month, the other being the appearance of the Christmas Star for the first time in 800 years. Sadly, I’m striking out with the Geminids myself because it’s raining this week. And this reminds me of a book I read several years ago about the 18th century quest to track the Venus Transit. Every 240 years or so, Venus transits the sun, which means that it will cross over between the earth and the sun. And this event happens in a pair 8 years apart. Back in the 18th century,…