This is Dudley Observatory’s Skywatch Line for Friday, June 12, through Sunday, June 14, written by Sam Salem.

On Friday, Sun rises at 5:16am and sets at 8:34pm; Moon rises at 2:45am and sets at 6:07pm. New Moon occurs at 10:54 pm on Sunday.

The waning crescent Moon joins up with Mars on Friday early morning in the constellation of Aries, the Ram. The Moon sits almost directly above Mars as they rise. The two bright stars of the Ram, Hamal and Sheratan, lie above the Moon and Mars. Spot the Pleiades star cluster (M45) in the constellation of Taurus, the Bull. It lies to the lower left of Mars.

Mercury, at magnitude 0, shines lower right of brilliant Venus and Jupiter in the western twilight. It’s not nearly as bright as the other two planets. Look for Mercury about 45 to 60 minutes after sunset. It sits about a little more than a fist at arm’s length to the lower right of Venus.

Venus and Jupiter, shine together in the west during twilight and then for about 30 minutes after full dark before setting. Venus is the brighter of the two at magnitude –4.0. Jupiter is a seventh that bright at magnitude –1.9. They slid by each other between the evenings of Monday and Tuesday this week. On Friday they are 3½° apart with Venus now higher than Jupiter.

Venus, Jupiter, and Mercury sit in the constellation of Gemini, the Twins. Spot Pollux and Castor upper right or right of Venus and Jupiter. Pollux is slightly the brighter of the two Gemini heads.

Mars, at magnitude +1.3, remains low in the eastern sky as dawn approaches. To locate it, position your telescope approximately three fists to the lower left of the more prominent Saturn. Even with high magnification, Mars will not reveal any discernible details. Currently situated approximately 201 million miles from Earth, Mars’ disk appears only 4” across in the sky.

Saturn, at magnitude +0.8, ascends approximately one hour prior to the onset of dawn. Observe it in the east-southeast as the first rays of sunlight illuminate the horizon. No other celestial body in the vicinity possesses a comparable brightness. Fomalhaut, its near-twin in luminosity, is located approximately three or four fists to the right of Saturn in the south-southeast direction.

Look east after the night is fully dark across the eastern sky for the rich stretch of the summer Milky Way through Cepheus, Cygnus, Aquila, and Scutum, from left to right. It goes up higher every hour and every week. The Milky Way runs horizontally under Vega, along the bottom edge of the Summer Triangle.

Watch Arcturus, very high toward the south these evenings. Spica sits about three fists at arm’s length below it and a bit right. Off to their right sits the dimmer Denebola, Leo’s

2nd-magnitude tail tip. The three stars form an almost perfectly equilateral triangle. All three sides of the triangle are close to 35°. This asterism is occasionally referred to as the Spring Triangle, complementing the Summer and Winter Triangles.