As the year is coming to a close, we can witness the last planetary conjunction for the year.
Jupiter and Mercury are coming closer in the evening sky. Normally Mercury is a very elusive planet to find, not because it is faint but because it is always very close to the horizon whenever it is visible – early morning or early evening. In the absence of a marker star or planet to locate Mercury, it could be a hard find. And that’s what makes this conjunction interesting.
Jupiter and Mercury are very close in the evening sky now, and if you watch just after the sunset from a location with a clear view of the western sky, you should be able to spot the planets without much difficulty. Venus is a little higher in the evening sky too shining brightly. Mercury now has an apparent magnitude of -0.7. To give a comparison, except for Sirius, the brightest star visible to the naked eye, no other star in the night sky appears much brighter than this. The proximity to Jupiter makes it easy to spot the planet. That’s all. And of course, the twilight might make it appear little fainter than what a -0.7 magnitude object should look like.
Here are a few screen-shots taken using Stellarium. This is taken for an observer in south Karnataka, India (about 13degrees North). However, if you are somewhere else, the same timings should work for you too; but remeber that the Moon is the fastest moving body in the Sky. So the relative position of the Moon (with respect to the planet pair) might be different than what these pictures show.
Here is the evening sky of 12/30/2008. (about 15 minutes after sunset)
Here is the evening sky on 12/31/08; About 15 minutes after sunset.
Notice the relative movement of Mercury and Jupiter. Also notice the crescent moon moving out of the view (in the screenshot) as it goes higher in the sky. In the sky, of course, it would appear larger and higher.
I managed to get a glimpse of the planets last night, since the clouds moved away from the western horizon just in time. Tonight, it is to be seen how the weather god Varuna, c0-operates :).
If you have clear evenings the next few days , do not forget to head out right after sunset and check out!