Northern Sky: Feb 3 - 16, 2018

Northern Sky  by  Deane Morrison 
Feb. 3-16 2018
 
As we approach the middle of February, the moon spends more and more time in the morning sky, and that's good for everybody who would rather see stars in the evening.
 
This is the best time of year to enjoy all the bright winter constellations I've been talking about. If you go out an hour after sunset, you'll see them in the southeast to south. Sirius is the brightest star of all, and it's also the lowest of the bright winter stars. Sirius is called the Dog Star because it dominates Canis Major, the larger of Orion's hunting dogs. In ancient times, people thought that during the summer, when Sirius appears nearer the sun in the sky, its heat combined with the sun's heat to produce the hottest days of the year, which were dubbed the dog days. Of course, Sirius has nothing to do with it, but when looking at it against a dark winter sky, it's easy to see how people could think that.
 
Sirius is also part of two well-known geometric arrangements of stars. One is the Winter Triangle. Besides Sirius, the stars in the triangle are Procyon, which is above and a little east of Sirius, and reddish Betelgeuse, which is a little west of Procyon. Then there's the Winter Hexagon. Again starting with Sirius, move around clockwise to Procyon, which is in Canis Minor, the little dog; then Pollux, the brighter Gemini twin; Capella, in Bootes the herdsman--this is the highest star in the hexagon; then Aldebaran, the eye of Taurus, the bull; and finally Rigel, in Orion.
 
In the morning sky, the planet show continues. The planets and neighboring stars are moving out of the southeast and into the south now. All three morning planets are rather low, but the highest, brightest and most western one is Jupiter. Moving to the left, or east, the constellation Scorpius has Mars, and below Mars is the gigantic red star Antares, the heart of the scorpion. The bright light to the lower left of Mars and Antares is Saturn. At this point, Mars isn’t especially bright, because it’s about 143 million miles away. But when Earth catches up to it this summer, it’ll be almost four times closer—just 36 million miles away. And pretty darn bright.
 
The moon wanes away to the new phase on February 15th, and on its way it visits the morning planets. Between the 7th and 8th it sweeps by Jupiter. Between the 8th and 9th, it passes Mars. On the 9th, the moon, Mars and Antares will make a nice trio of objects. On the 11th, the moon will be right above Saturn, and Saturn will be right above the lid of the Teapot of Sagittarius. On the 12th, the crescent moon will be sitting in the curved line of stars known as the Teaspoon, which hangs above the handle of the Teapot. On the 13th, the moon will be a lovely thin crescent. On the 16th, a young moon of the next cycle appears in the west, in the sun's afterglow. You'll have to look about half an hour after sunset to see it, and you may catch Venus to the lower right of the moon. This month, Venus is just starting a climb into the evening sky.
 
Also in the evening, look for the pale and elusive zodiacal light in the west as soon as the sky gets dark. The zodiacal light appears as a broad finger, or cone, of light extending up along the sun's path. It's caused by sunlight reflecting off dust in the plane of the solar system. You need dark skies to see it, and if you do, count yourself among the fortunate few.