Venus Transit June 5/6 2012

On June 5 and 6 2012, Venus made a rare transit across the face of the Sun for the second time in a decade, and the last time for more than 100 years. The following is from a NASA description:

The transit or passage of a planet across the face of the Sun is a relatively rare occurrence. As seen from Earth, only transits of Mercury and Venus are possible. On average, there are 13 transits of Mercury each century. In contrast, transits of Venus occur in pairs with more than a century separating each pair.

The last Venus transit was in 2004 so the second event of the pair will occur on Wednesday, June 6 (Tuesday, June 5 from the Western Hemisphere). The entire event will be widely visible from the western Pacific, eastern Asia and eastern Australia. Most of North and Central America, and northern South America will witness the beginning of the transit (on June 5) but the Sun will set before the event ends. Similarly, observers in Europe, western and central Asia, eastern Africa and western Australia will see the end of the event since the transit will already be in progress at sunrise from those locations.

We decided to take an exploratory look at this, following a suggestion from Brian Josephson,

The time period that would seem to be relevant is difficult to specify, and we simply took the period of the transit plus a few minutes at both ends. The figure below is marked to show Contact I and Contact IV. There is a fairly persistent trend during the transit, but the deviation is not significant. We note that since this is an exploratory look, it does not warrant statistical interpretation. Single events are in any case not viable as tests of the general hypothesis of correlation between "global events" and deviations in GCP data. Bearing this out, the results for an exploration of the Venus transit in 2004 showed flat null results.