Winter can be a challenging time to enjoy the night sky, but bundle up and let the cold, clear winter nights entice you outside. The most obvious difference between the skies of winter and summer is the winter predominance of bright stars, many in very distinctive, eye-catching patterns.
The showpiece of winter is the constellation Orion, the Hunter. Look toward the south at 10 pm in early January, and you’ll easily spot Orion’s three evenly spaced and equally bright belt stars angled upward toward the right. Two bright stars above the belt mark his shoulders. The left one – his right shoulder – is Betelgeuse and is distinctly reddish. Below the belt two stars mark his knees, Rigel being the brightest. Between the belt and the knees, you will see a line of three stars on the left, hanging downward. This is the hunter's sword. Note that the middle star looks fuzzy. This is actually the Great Orion Nebula, a cloud of gas and dust where stars are being born. By early February Orion will be in the south around 8 pm.
You can use Orion’s belt to find two other constellations. Imagine a line going through the stars and continuing to the right. The first bright star you come to is a very reddish Aldebaran. It marks the eye of Taurus, the Bull, and is at the end of a “V” of stars, its bottom to the right, that outlines his face. Heading across the sky in the other direction, you’ll come to Sirius, the luminary of Canis Major, the “Big Dog.” Sirius is the brightest star in our night sky.
Early January's dawn skies will offer a nice treat, when Venus will be close to Saturn and pass within ½-degree (the apparent diameter of the Moon) of the ringed planet. Here are some of the highlights:
- Tuesday, January 5, at 6:30 AM. Look for the pair in the southeast. Brilliant Venus will be highest, with Saturn just over four degrees to its lower left. You should also spot the reddish star Antares below and a bit to the right. To the upper right you’ll find a crescent Moon, and farther right and higher in the sky red Mars, with the star Spica close by in the south. Bright Jupiter will be even higher and in the southwest.
- Wednesday, January 6, at 6:30 AM. The lovely crescent Moon will be closer to Venus, and Saturn will be less than four degrees from Venus.
- Thursday, January 7, at 6:30 AM. The slender Moon will be left of Saturn. The distance between Saturn and Venus will continue to shrink, reaching less than one degree.
- Friday, January 8. Making their closest approach, Saturn and Venus will separated by less than ½-degree. Then on each of the following mornings, Venus will be higher and farther away.
As the weather warms, consider joining the Albany Area Amateur Astronomers for a Star Party at the Landis Arboretum. These events are free and open to the public. (Donations to the Arboretum are always gratefully accepted.) After a brief orientation to the night sky, participants are invited to view celestial phenomena through several telescopes. Our schedule will be published in the Arboretum’s 2016 Calendar of Events and is also available both on the Landis website and our own website (http://dudleyobservatory.org/AAAA). Registration is suggested because Star Parties are canceled if the skies are mostly cloudy. For more details or to register, call me at (518) 374-8460.