Skywatch Line for Friday, June 5, through Sunday, June 7, written by Sam Salem
This is Dudley Observatory’s Skywatch Line for Friday, June 5, through Sunday, June 7, written by Sam Salem.
On Friday, Sun rises at 5:18am and sets at 8:30pm; Moon rises at 12:04am and sets at 9:45am.
Last-quarter Moon occurs at 6:01 am Monday morning. The Moon rises almost due east around 1 am, on Sunday night/Monday Morning, lower right of the Great Square of Pegasus. The Square stands on one corner. Its top-right side points diagonally down to the Moon.
Mars, magnitude 1.3, rises roughly an hour before the Sun. Mars is 12° above the eastern horizon, half an hour before sunrise. Saturn, brighter, shining at magnitude 0.8, lies west of Mars. Mars remains very low in the east as dawn brightens. Look for it about 3 fists to the lower left of Saturn. Looking at Mars through a telescope will show little more than the view with binoculars as the planet is just 4” across, with no surface detail visible at that size.
Saturn ascends approximately 30 minutes prior to the initial appearance of dawn. Observe it positioned low in the eastern sky as the dawn’s illumination intensifies. Flickering star Fomalhaut is nearly identical to Saturn in brightness. Fomalhaut is visible in the south-southeast direction, approximately three or four fists to the right or lower right of Saturn.
For months Venus and Jupiter have been approaching each other. On Friday night they shine just 4° apart. Spot Mercury 14° to their lower right. That’s a little more than a fist at arm’s length.
Venus and Jupiter will shine just 1.8° apart on Monday, then 1.6° apart on Tuesday when they’re in conjunction. That’s about a finger’s width at arm’s length. Venus and Jupiter shine together in the west during twilight and for about 40 minutes after full dark. Venus is the lower and the brighter of the two, at magnitude –4.0.
Venus, Jupiter, and Mercury are in the constellation Gemini. Spot Pollux and Castor above or upper right of Venus and Jupiter. Pollux is slightly the brighter of the two Gemini heads. Spot Mercury, about magnitude –0.5, far to the lower right of brilliant Venus and Jupiter in the west. Look for it about an hour after sunset.
After sunset, watch the Big Dipper hanging downward by its handle, positioned high in the northwest sky. The central star of the Big Dipper handle is Mizar, accompanied by the smaller Alcor. Mizar and Alcor are a famous naked-eye double star pair located in the middle of the Big Dipper’s handle in the constellation Ursa Major. The brighter of the two is Mizar, and its faint companion located just to the northeast is Alcor. Both Mizar and Alcor are multiple-star systems. Mizar consists of four stars in two binary pairs orbiting one another. Historically, it was the first double star ever discovered through a telescope in 1617, and the first binary star system photographed in 1857. Alcor consists
of a pair of binary stars. Astronomers confirmed they are gravitationally linked to the Mizar system in 2009.