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A Gathering of Planets

© Gregg Pasterick

The big deal of June night skies has to be the gathering of planets late in the month. Mercury, Venus and Saturn are the planets in question, and, given that the inner planets are involved, it obviously takes place near the sun, in this case, in the gloaming at the end of the day. (I got to use the word 'gloaming' again!) It's also an interesting notion of perspective as we look at those planets nearer our star swarming with Saturn, which is way, way out, on the other side of it.

The fun gets started at the beginning of the month when Saturn, almost making a straight line with Castor and Pollux, sits in the dusk sky to the upper left of Venus. Each night thereafter, the ringed planet and the bright stars of Gemini lose just a little more altitude while Venus, like a hot air balloon in no hurry to get anywhere, rises up to meet them. By the middle of June, Mercury shows its face low in the sky, to the lower right of Venus.

Just a day before the Summer Solstice on the 20th (which has nothing to do with this gathering of planets, but certainly gives it a sense of occasion, don't you think?), Venus, Saturn, and Pollux make a nice triangle, with Venus 5 1/2 degrees away from each of the other two. At the same time, Mercury is just 2 1/2 degrees away from Venus. Saturn then drops its pants and slides on the ice, dropping past Venus and Mercury on the 24th, 25th, and 26th. The three planets are all within 2 degrees of each other during these three nights, and they are nearly in a straight line on the first two nights. They occupy the smallest amount of space on the 25th, when they are within an area of 1.37 degrees. Venus and Mercury are nearest each other on the 27th, when they are only about 0.1 degree apart. (It brings Groucho Marx to mind who, in response to his dance partner's cries of, "Closer. Closer!" says, "If I get any closer I'll be behind you.")

From the 24th until the first of July, while Saturn drops to a distance of 7 degrees away from the inner planets, Venus and Mercury remain within 1 degree of each other. During all this, Saturn and Mercury both shine at magnitude 0.0, while Venus is a blinding magnitude -4.0.