Winter night Skies
This article appeared in the January 20, 2012 edition of the Davis Enterprise.
Everyone is invited to the Sat. Jan. 28, 2012 meeting of the Davis Astronomy Club at Explorit Science Center at 3141 5th St. starting at 7:00pm. You do not have to pay any dues to be a member of the Davis Astronomy Club. If you are interested in astronomy, you are welcome to attend.
This month we will discuss the winter constellations visible in the night sky. We will discuss the Orion constellation in depth and also talk about some of the deep sky objects found within the boundaries of the constellation. We will also use telescopes to look at objects in the night sky, weather permitting.
The Orion constellation is one of 88 constellations formally recognized by the International Astronomical Union. It is the second most identifiable star grouping in the sky (after the Big Dipper). For northern latitude observers, Orion is prominently visible in the night sky from late fall to early spring.
The Orion constellation, named after the Greek mythological character Orion, is also known as the Hunter because the bright stars in the constellation look like a hunter with one raised arm and one outstretched arm. Its most recognizable feature is the three stars in a straight line in the middle of the star pattern, forming the hunter’s belt. Fainter stars form the hunter’s sword hanging from his belt.
The main stars in Orion’s constellation are:
• Betelgeuse (Arabic for armpit) is a very bright variable red giant star forming Orion the Hunter’s right shoulder. This dull red star’s brightness varies from magnitude. +0.4 to +1.3. It is the ninth brightest star in the sky, and is part of the Winter Triangle along with stars Sirius and Procyon.
• Rigel (Arabic for foot) is a very bright blue-white giant forming Orion’s left knee. It is the brightest star in the Orion constellation with magnitude. +0.08, and it is a visual binary. It is the sixth brightest star in the sky, and is part of the Winter Hexagon, along with stars Sirius, Procyon, Pollux/Castor, Capella, and Aldebaran.
• Bellatrix (Latin for female warrior) and Saiph form Orion’s left shoulder and right knee, respectively.
• Alnitak, Alnilam, and Mintaka are the three stars (from left to right) in a line that forms Orion’s belt. Mintaka (Arabic for upper end of girdle) is a visual binary.
Telescope viewing will be available after the presentation, weather permitting. Very bright Venus (mag. –3.9) will be setting in the west after 8pm. As bright Jupiter (mag. –2.3) will be setting around 11:30pm. The Orion Nebula will be a great treat to view through a telescope or binoculars. We will also look at the mountains and craters on the moon, which will be in first quarter phase and will be setting around 11pm
Explorit’s coming events:
• Explorit’s newest Exhibition, “Forces of Nature” is open the first full weekend of every month from 1:00 to 5:00 p.m. This exhibition welcomes the public back to our 3141 5th Street Nature Center and will feature some of the best of Explorit’s past exhibits.
• The Davis Astronomy Club will meet at Explorit on Saturday, January 28, 2012 at 7:00 pm.
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Explorit Science Center is located at 3141 5th St. and is open to the public every first Saturday and Sunday of the month. For more information call (530) 756-0191 or visit http://www.explorit.org, or “like” us on Facebook at www.facebook.com/explorit.fb.
