Minnesota Starwatch for July 2021

Deane Morrison
University of Minnesota, Extension

 Venus glimmers in the sun’s afterglow, where it will stay for months to come. Look for the planet low in the west-northwest about 40 minutes after sunset. The best days may be the 11th and 12th, when a young moon hovers nearby.

     In the southern sky, the summer stars have taken center stage. Grab a star chart—or find one online—go out at nightfall, and start by locating the Big Dipper in the northwest. Follow the curve of its handle to brilliant Arcturus, a star whose path cuts down through the plane of the Milky Way. Arcturus anchors the kite-shaped constellation Bootes, the herdsman.

     Moving eastward, we first encounter Corona Borealis, the Northern Crown, accentuated by its bright star Alphecca (or Gemma). Next comes an hourglass of stars outlining upside-down Hercules. 

     Then we meet the large Summer Triangle of stars. Brightest is Vega, in Lyra, the lyre. To Vega’s lower left is Deneb, the tail of Cygnus, the swan. Deneb is also the brightest star in the Northern Cross, whose long section extends below Vega. Farther below Vega shines Altair, in Aquila, the eagle. East of Altair, little Delphinus, the dolphin, seems to leap toward a dark sea. Above it floats skinny Sagitta, the arrow.

     Low in the south, gigantic red Antares marks the heart of Scorpius. Just east of Scorpius sits the Teapot of Sagittarius, with its spout pointing toward the scorpion’s tail.

     By month’s end, Saturn and Jupiter, in that order, will be rising in the southeast before midnight. Look for them below Altair. Or catch them in the southwestern predawn sky; note that they form a triangle with Fomalhaut, the lone bright star in Piscis Austrinus, the southern fish. Earth is catching up to both planets in the orbital race and laps them in August. 

     July’s full moon rises within an hour of perfect fullness the evening of the 23rd. Though not designated a supermoon, it will still be close, and thus bright as well as quite round.