Monday, January 02, 2012

Return of Venus

Since November, stargazers have noticed a bright "star" in the southwest after sunset. This is the planet Venus. After passing superior conjunction, it is ascending in the evening sky. Venus will steadily gain in both height and brilliance until it becomes a striking object in March and April. Right now it is still too remote to be a worthwhile telescopic object. As Venus nears Earth, however, its crescent will become large and slender--a nice sight in a telescope.
This appearance of Venus resembles those of 1972, 1980, 1988, 1996 and 2004. Every eight years, Venusian history virtually repeats itself. There will be an important difference in 2012, however, just as there was in 2004. When inferior conjunction occurs early in June, Venus transits the solar disc. Prior to 2004, inferior conjunctions in this series occurred too late in June for a transit.
It was a real challenge to see the 2004 transit, because it was ending just as the sun was rising here. Since the sun was still low, it was very difficult to get it into a telescopic field of view. I noticed sunlight entering through an upstairs window, but had to open the window and hold the telescope in an awkward position, halfway outside. Finally, I was able to project the sun's image onto a white piece of paper. Immediately I noticed a dark spot near the edge of the sun--Venus. I succeeded--albeit barely--in seeing an extremely rare astronomical event. I hope to see it again in June of this year.