The nights of July are short, but they are packed with sky happenings and objects. All five naked-eye planets are visible at some point during the month, with Venus ending its long run as the morning star. It is barely visible in early twilight at July's start, then disappears by the middle of the month.
The “dog days” of summer are upon us. They get their name from the Dog Star, Sirius. The brightest star in the night sky, it is immersed in the Sun’s glare at this time of year. Because of that, ancient skywatchers named this period in the star’s honor.
The Moon is full at 1:40 a.m. CDT today. The full Moon of July is known by several names, including Hay Moon and Thunder Moon. Since the first people landed on the Moon during the month of July, we might someday add “Apollo Moon” to the list.
The evening skies of summer feature Aquila, the Eagle, whose brightest star, Altair, is easy to see. But the constellation also hosts one of the faintest stars yet discovered. Known as Van 17, 2011
Hercules stands directly overhead this evening. Four moderately bright stars form a lopsided square that represents his body, while his head points southward. He is surrounded by monsters he has dispatched, including Hydra, the water snake.
The planet Mercury pops into view about 30 or 40 minutes after sunset. It’s bright, but it’s also quite low in the sky, so it’s tough to see through the lingering twilight. Any buildings or trees along the horizon will block it from view.
The tiny constellation Corona Borealis, the northern crown, stands high atop the sky as darkness falls this evening. This prominent semicircle of stars is wedged between the bigger constellations Bootes and Hercules.
Vega, the brightest star in the summer sky, stands high in the sky as darkness falls. It’s in Lyra, the harp. Vega is heavier, brighter, and hotter than our own Sun, and about four billion years younger.