June 2002

By Steve Stefanik

June begins with Jupiter and Venus prominently poised above the western horizon at nightfall. This evening the pair are within 2 degrees of each other side by side mimicking the Gemini twins, Castor and Pollux, which are located directly above. However, both Venus and Jupiter are much brighter at magnitude –4.0 and –1.9 respectively than either +1.6 magnitude Castor and +1.2 magnitude Pollux. Venus will pass Jupiter and pull to within 1 2/3 degree above it on Monday evening. This month Venus will be more than 25 degrees in altitude at sunset, the highest it will be all year. At the beginning of the month, Venus and Jupiter set almost 2 ½ hours after sunset but

Jupiter keeps appearing lower and lower with each passing night so that by month’s end it sets 50 minutes after the sun goes down.

Mars is the only other planet remaining from last month’s planetary conjunction and you have to look for it 45 minutes after sunset so that it is not in the glare of the sun. It is more than 15 degrees below and the right of Jupiter, very small, and very dim.

June is also the best month to "see" the planet Pluto. It reaches opposition on the night of June 6-7 when it is at its brightest +13.8 magnitude but you’ll need a telescope with at least an 8 inch aperture, a good star map, and a lot of patience to see it move even slightly with respect to the background stars.

The only other planet that can be seen is Mercury. You may catch a glimpse of it low in the east-southeast about 45 minutes before sunrise. The best time to see it is when it reaches it’s greatest elongation from the sun on the 21^st , when the summer solstice will occur at 9:24 a.m. EDT later that morning, the first day of summer!