Opinion

The chameleon constellation

Thursday, November 5, 2009

Before we leave the northern sky, lets take a closer look at what I call the "chameleon constellation," Cassiopeia, the Queen. By that I mean, at different times of the year, Cassiopeia will look different. For part of the year she looks like the letter "M" and six months later she will look like a "W."

Cassiopeia is a circumpolar constellation, it circles the north pole and never sets below the horizon; our good friends in the deep southern hemisphere can't see her at all.

Right now, and all through November, Cassiopeia is located high in the northern sky and looks like the "M." She is directly across Polaris, the North Pole star, from the Big Dipper. The two circle each other around the pole all year long.

Go outside at about 9 p.m. local time and look north. If you know how to find the Big Dipper, follow the pointer stars to Polaris and continue on a little to the right to find the "M" of Cassiopeia.

In fact, you can use Cassiopeia and the Big Dipper to find another of the constellations mentioned in the story of Andromeda and Perseus, Cepheus, the King. He looks like a box with a pointy cap on top and the point of the cap is always near Polaris. Also the "prongs" of the "M" of Cassiopeia point toward Cepheus.

The northern end of the Milky Way passes through Cassiopeia making it a wonderful playground for your binoculars and telescope. Lots of planetary nebula and star clusters to find there. Bundle up warm against the cold, bring along a jug of hot chocolate (or coffee if you are so inclined), and enjoy spending some time with the queen and her court.

Six months from now, in May, when it will hopefully be a little warmer, go outside again at 9 p.m. local time and look north. Cassiopeia and the Big Dipper have changed places. The Big Dipper is high and Cassiopeia is low and now looks like the letter "W."

For the last few weeks we here in Southwest Nebraska have been getting the short end of the stick as far as observing passes of the International Space Station. They have all been early in the morning and are very short, only two or three minutes. Next week there will be a change of viewing times into the evening after sunset, but they will still be short passage times, at least for now.

On a personal note I would like to thank all those who found my Twitter page and signed up to be followers. It is there I am able to put some last-minute information about astronomical events, such as the pass times of the ISS. If you missed the information, simply establish a Twitter account, look the The Stargeezer (it may be in lower case) and click on "follow" and check frequently for astronomical updates.

SKY WATCH: The moon was full on Monday, Nov 2, and, at least for the next few days, will possibly interfere with any early evening viewing. Third quarter moon on Monday, Nov. 9. The stars of the Summer Triangle are low in the west in the early evening while Pegasus and company are high overhead. The bright object in the southeast is Jupiter.

At about 2 a.m., if you are an early bird or just can't sleep, the moon and Mars will have a nice conjunction just above the eastern horizon. The following day, Nov. 10, the moon will meet with Regulus, the brightest star in Leo, the Lion. The pair will clear the eastern horizon at 2 a.m., but a better viewing time will be between 3 a.m. and dawn. Venus is sinking lower and lower each day in the eastern early morning sky and by Nov. 17 or so will be lost to view.

Next time: More astronomical blathering.

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