Skywatch Line for Friday, June 16, through Sunday, June 18, 2023

This is Dudley Observatory’s Skywatch Line for Friday, June 16, through Sunday, June 18, written by Sam Salem.

On Friday, Sun rises at 5:16am and sets at 8:36pm; Moon rises at 3:47am and sets at 7:37pm. New Moon occurs at 12:37am on Sunday.

Venus, at magnitude –4.5 in Cancer, is the brilliant “Evening Star” in the west from twilight into late evening. It’s not as high in the dusk as it was a couple weeks ago, but it doesn’t set until more than an hour after full dark. Venus will become a bigger, thinning crescent dropping lower until it’s lost from sight in mid- to late July.

Mars, at magnitude 1.7, also sits in the constellation of Cancer. It glows weakly to Venus’s upper left, by a slowly shrinking distance of 5½° on Friday evening. Mars and Venus will reach a minimum separation of 3.6° on June 30th, then they’ll start to draw apart again as Venus plunges down toward the sunset.

Jupiter, at magnitude –2.1 in Aries, shines low in the east before and during early dawn.

Saturn, at magnitude +0.9 in dim Aquarius, is nicely up in the southeast before dawn.

The Summer Triangle stands high in the east after dark as we count down the last few days to summer. The Triangle’s top star is bright Vega in the constellation of Lyra the Harp. Deneb, in the constellation of Cygnus the Swan, is the brightest star to Vega’s lower left by 2 or 3 fists at arm’s length. Look for Altair a greater distance to Vega’s lower right. Altair, in the constellation of Aquila the Eagle, is midway in brightness between Vega and Deneb. The Milky Way runs across the lower part of the Summer Triangle from side to side. As night progresses, look lower left of Altair for little constellation of Delphinus, the leaping Dolphin.

Look south-southeast after dark for orange Antares, the brightest star in the constellation of Scorpius. Antares is considered “the Betelgeuse of summer.” Both Antares and Betelgeuse are 1st-magnitude “red” supergiant starts. Around and upper right of Antares are the other, whiter stars of upper Scorpius, forming their distinctive pattern. The rest of the Scorpion curls down toward and along the horizon.

Spot Arcturus, the brightest star in the constellation of Boötes, way up high toward the south. Three fists below locate Spica, the brightest star in the constellation of Virgo. A fist and a half to Spica’s lower right, four-star Corvus, the Crow, is heading down and away.

Leo the Lion, the mostly a constellation of late Winter and Spring, has not gone yet. As twilight ends look upper left of Venus and Mars for Regulus, Leo’s brightest and now lowest star. It is the forefoot of the Lion stick figure. The Sickle of Leo, the Lion’s front part, extends upper right from Regulus. The Sickle is heading for the two planets. The rest of the Lion’s constellation figure extends for almost three fist-widths to the upper left, to his tail star Denebola, the highest. Leo will soon be treading off into the sunset.