Observing Calendars

December Observing Calendar   Last month we discussed the mythology of Andromeda. The remaining part of that story starts with the Pleiades M45. The Pleiades is a very bright, open cluster 410 light-years away with observable nebulosity. The hot young stars in this cluster are still actively making new stars as evidenced by the nebulosity easily seen in binoculars and small telescopes. The myth of Perseus covered last month continues with the Pleiades. They were the nymphs who gave him the winged sandals and showed him the way to find Medusa (another extension of the myth). The head of Medusa rests in his hand. The variable star Algol is said to be her eye which "winks" from time to time. Algol, a variable star, has a period of three days which means it changes its brightness every three days and can be seen to dim and brighten with the naked eye. The sword of Perseus points to the double cluster of Perseus. This double cluster is visible to the naked eye on a clear night. Look carefully between the top of Perseus and the lower "W" of Cassiopeia. Two soft glowing patches can be seen quite close to each other. Binoculars and small telescopes reveal a pair of spectacular open clusters, NGC 869 & NGC 884. NGC 869 on the left is considerably younger than its companion, estimated to be only six million years old versus 14 million for NGC 884. They are estimated to be 7,200 and 7,500 light-years from earth respectively. Many interesting objects for small telescopes and binoculars can be seen from Cassiopeia along the star-rich lanes of the Milky Way. Grab your binoculars or small telescope, lawn chair, and a blanket. Many beautiful clusters and interesting star patterns await you. Now is a good time to check out the marvels of the great constellation Orion. Orion is the star nursery of the northern hemisphere. M42 is easily spotted with the naked eye just off Orion's sword. A challenging visual object, but an astonishing CCD image is the Horsehead (B33) and Flame Nebula ( NGC2024) just off the northeastern star in the belt.