This summer belongs to the planets, with four of the five visible planets gracing the evening sky.
Although it feels like summer, the official astronomical beginning of summer occurs on June 21. On this day the Sun takes its northernmost path across the sky bringing a very long day and short night. Also, darkness doesn’t occur until well after 10 pm. Stargazers must be patient while evening twilight slowly gives way to nightfall.
There is one celestial object that doesn’t require waiting for complete darkness. Looking westward, Venus easily shines through evening twilight. Venus has been steadily ascending throughout spring, placing it in prime position for viewing this month.
At month’s onset, Venus resides in the northwestern sky, but those who observe Venus all month will notice it gradually moving southward. This motion is due to Venus rounding the curve of its orbit and in July the brightest planet begins its slow descent back towards the Sun. But don’t count Venus out; our closest neighbor remains visible all summer.
Joining Venus in the west mid-month is the smallest planet, Mercury. On June 14, the crescent moon sits just to the left of Mercury. Both sit low above the horizon shortly after sunset. Mercury gains altitude the last half of June, but never gets very high due to its tight orbit around the Sun.
Two more visible planets, Jupiter and Saturn occupy the southeastern sky this month. Jupiter is the southerly most planet and easily outshines all stars in its vicinity. Saturn, more easterly, is nestled among the bright cloudy regions of the Milky Way galaxy. Saturn is at opposition this month, making it in line with Earth and the Sun and also at its brightest for the entire year. Use the Moon for finding Saturn on June 27, when it sits very close just left of Saturn.
Next month, Mars joins Mercury, Venus, Jupiter and Saturn in the evening sky for another great month of planetary observing.