In the Sky This Month

The Perseid meteor shower will be at its best the next couple of nights. Unfortunately, the gibbous Moon will be in the sky during the best hours for meteor watching. That will spoil the view of all but the brightest meteors.

The planets Venus and Jupiter, the brightest objects in the night sky after the Moon, are crossing paths in the early morning sky. Jupiter is pulling away from the Sun as seen from Earth, while Venus is dropping toward it. Venus is the brighter of the planets.

Deneb, which represents the tail of Cygnus, the swan, is high in the east-northeast at nightfall. Deneb might be the brightest star that is easily visible to the unaided eye. It is up to 200,000 times the Sun’s brightness.

Altair is a close neighbor, just 16.7 light-years away. Only about 50 star systems are closer. And Altair is quite bright, so it’s easy to see. It stands high in the southeast at nightfall, at the lower right corner of the bright Summer Triangle.

The Moon is about 95 percent full tonight, so its glare overpowers many faint stars. But three stars are quite easy to find: Vega, Deneb, and Altair – the Summer Triangle. The trio stands high in the eastern sky at nightfall, and directly overhead later on.

The brightest star of summer nights is diving toward the western horizon. Arcturus, the leading light of Bootes, the herdsman, is about half way up the western sky at nightfall. It will drop lower each night.

Equuleus, the little horse, gallops near the winged horse Pegasus. Pegasus is outlined by a large diamond of four bright stars that’s in the east and northeast by 10 p.m. Equuleus occupies a fairly dark region of the sky well to the upper right of the diamond

Antares, the heart of the scorpion, huddles close to the Moon tonight. Antares consists of two stars. The star we see is many times bigger and heavier than the Sun, and it probably is 50,000 to 100,000 times brighter than the Sun.

Mars appears to have a shadow this evening. It is a faint star with a lyrical name: Zavijava. Mars looks like a fairly bright orange star, quite low in the west at nightfall. Zavijava is almost touching it. Binoculars will enhance the view.

The Moon is at first quarter today at 7:41 a.m. CDT. It appears at a right angle to the line between Earth and the Sun, so sunlight will illuminate half of the Moon’s Earth-facing hemisphere.