This is Dudley Observatory’s Skywatch Line for Friday, June 28 through Sunday, June 30, written by Sam Salem.
On Friday, Sun rises at 5:16am and sets at 8:36pm; the waning crescent Moon rises at 2:26am and sets at 4:16pm. The crescent Moon swings to the south of the Pleiades star cluster on Saturday. The waning crescent moves to the north of Aldebaran, the brightest star in constellation Taurus the Bull, on Sunday night.
Mercury shines at magnitude 0.7. In close proximity is Mars. While nearly as high as Mercury, at magnitude 1.8, the red planet is much fainter which makes it more difficult to pin down. Mercury and Mars set around 10pm. Jupiter, the magnitude –2.6 beacon in southern constellation Ophiuchus, lies low in the southeast, visible soon after sundown. Antares, much fainter at magnitude +1.0, twinkles 9 degrees to its right. Jupiter is highest in the south around midnight with orange Antares to its lower right. Jupiter and Antares form a wide, flat, almost isosceles triangle with Delta Scorpii to their right. In a telescope Jupiter is still a good 46 arc-seconds wide. Jupiter rises at 6:57pm and sets at 4:07am. Saturn, at magnitude 0.1, rises a few minutes after 9pm in eastern constellation Sagittarius.
Venus, at magnitude –3.8, clears the east-northeast horizon less than one hour ahead of the Sun. Venus shines in front of the constellation Taurus in late June and early July. Both Aldebaran and Venus will be near the sunrise. Venus is much, much brighter. You’ll need an unobstructed horizon to see them. The Pleiades star cluster, a tiny, misty dipper in a dark-enough sky, is fainter still. You’ll need to be up before dawn’s first light, to see the Pleiades with the eye alone.
If you have a dark enough sky, try to find the Milky Way as it now forms an arch across the eastern sky as evening grows late. It runs all the way from below Cassiopeia in the north-northeast, up and across Cygnus and the Summer Triangle in the east, and down past the spout of the Sagittarius Teapot in the south-southeast, where it’s brightest.
With the Moon absent from the evening sky this weekend there’s plenty to see on late June nights. The magnificent Hercules globular cluster, M13, is now ideally positioned near the meridian at midnight. Home to a half million stars, M13 is faintly visible to the unaided eye at a dark rural site. In binoculars it looks like a fuzzy “star”. A small telescope under 3-inches aperture provides a pleasing image that will reveal a few cluster members popping fleetingly into view. In a mid-size scope, M13 is truly a sight to behold. Uncountable stellar points are arrayed against a glowing core of densely packed starlight. Try different magnifications to find one that best shows the cluster in your telescope. Under dark skies, see if you can spot the little galaxy NGC6207, situated less than ½ degree north-northeast of M13’s center. At magnitude 11.4, NGC6207 is something of a challenge for moderate-sized scopes. NGC 6207 is a spiral galaxy. It was discovered by William Herschel in 1787. NGC 6207 is located at about 30 million light years from earth.