Summer evenings offer the most glorious view of the Milky Way of the entire year. The glowing band of our home galaxy arcs from Sagittarius and Scorpius in the south to the graceful outline of the swan overhead to the west of Cassiopeia in the north. Although it’s not visible from most light-polluted urban areas, under dark country skies it offers a magnificent sight.
This Week's Stargazing Tips
August 2: 61 Cygni
After the Sun, the first star whose distance was accurately measured was 61 Cygni. It is part of Cygnus, the swan, which soars high overhead this evening. 61 Cygni is about 11 light-years away. It appears fairly close to Deneb, the swan’s tail.
August 3: Delta Cephei
Delta Cephei is one of the leading lights of Cepheus, the king, which stretches from north to northeast at nightfall. The star is unstable, so it pulses in and out like a beating heart. Astronomers recently discovered that it has a small, close companion star.
August 4: Moon and Uranus
With binoculars, you can spot the planet Uranus before dawn tomorrow, above the Moon. It forms a tight triangle with two slightly brighter stars in the constellation Pisces. All three should fit in your binocular field of view.
August 5: Pegasus
Pegasus, the flying horse, rises in the east in early evening. Look for a large square of four bright stars known as the Great Square. The stars that represent the horse’s head and forelegs stretch above and to the right of the square.
August 6: Last-Quarter Moon
The Moon is at last-quarter tonight. The name is a bit misleading, because sunlight illuminates half of the visible lunar disk. The “last-quarter” moniker means that the Moon has completed three quarters of its monthly cycle of phases.
August 7: Moon and Aldebaran
The Moon slides past two bright orange stars over the next few nights. The first is Aldebaran, the eye of Taurus, the bull. It is to the lower left of the Moon at first light tomorrow. The other is Betelgeuse, which is far below Aldebaran.
August 8: Quick Change
A star in the constellation Sagitta, the arrow, which is high in the east at nightfall, is changing before our eyes. Over the past 60 years, FG Sagittae has turned from blue to white to orange, indicating that it has puffed up and gotten cooler.
Check last week's tips if you missed a day.