Wednesday, February 13, 2008

Winter Skies

I finally got out to do some astronomy with the guys last weekend. Because my rehearsals are at night, and concerts are usually on Saturday night, the night the club has its dark-sky outings, I don't get a chance to do much astronomy in the winter. But that's not the only problem. While winter has the advantage that you don't have to stay up very late to wait for it to get dark (the sun sets here at about 5:30 pm now), I hate working in the cold. When you are viewing something at the scope, you just stand there, not moving very much, and you freeze even if the temperature isn't that low! Plus the metal equipment is very good at conducting the cold to your hands. I wear bikers' fingerless gloves in order to be able to turn the focus knob and such while keeping my hands as warm as possible. Last Saturday, I ended up with a ski hat and jacket on, plus the gloves and a scarf, and the temp only went down to about 52 degrees. And I wasn't the only one all bundled up like that. But it was a good night for seeing, at least until about midnight when I quit—relatively warm, dry, and still.

The winter skies offer some of the greatest glories of the universe for our viewing pleasure. At the top of the list is the Orion Nebula (M42) which can be readily seen by even a small telescope, it is so bright. I am awed by this spectacle every time I view it and Saturday night I spent a lot of time searching its depths for more details. I tried to figure out which neighboring "star" was M43, de Mairan's Nebula, and think I finally got it. In my scope, and most of the other scopes that were out, you can't see the nebulosity around M43, just the bright center, due to the light pollution coming from Los Angeles. (More on that later.)

I also explored the other parts of Orion's sword including NGC 1980 and 1977 (both emission nebulae), and 1981 (an open star cluster). Again the nebulae are very hard to detect, so I settled for locating the correct star pattern. My goal was to learn more about the winter sky and maybe soon (when I go up into the Sierras) I will be able to really see them in all their splendor.

I then moved on to other Messier objects in the same vicinity including M41, 46, 47, 48, and 79. 79 is a globular cluster, i.e., a tight group of stars that are gravitationally bound, with a dense center and less dense fringes. These look like fuzz-balls in my scope and 79 was particularly small and faint. I never would have found it without help from one of the guys. Unlike most of the objects in Messier's Catalog which are members of our galaxy, 79 has the further distinction of being an "immigrant" from a former dwarf galaxy that has been eaten up by our Milky Way.

41, 46, 47, and 48 are all open clusters of stars and as the name suggests, their members are more spread out. The famous Trapezium of the Orion Nebula is an open cluster. Saturday night we could see two of the fainter stars in the Trapezium in the larger telescopes (14- and 15-inch). Open clusters show up very nicely in my small scope (5-inch) but the most famous one of all, the Pleiades, M45, is so spread out, it is best viewed with binoculars. If your eyesight is good, you can see this one with the naked eye. Another cluster that is viewable with the naked eye is the Beehive Cluster, M44.

But alas, these wonderful sights are becoming dimmer and dimmer due to the increase of outdoor night lighting in my area. When I can no longer see Orion or Sirius in the winter night sky, I will cry. Our club, the South Bay Astronomical Society, has in the past worked to decrease the amount of new lighting installed especially at the Port of Los Angeles. Together with the local Audubon Society and others, they managed to convince the Powers That Be to install blue lights on the Vincent Thomas Bridge instead of glaring "skytracker" lights and floodlights.

I googled "Lights Out" last week to see what information I could get on the book, but discovered instead, Lights Out San Francisco and Lights Out America. The idea is simple, just try to get everyone to turn off their lights, especially outdoor lights, for one hour as a way of protesting light pollution. They did this with some success last October 20th in San Francisco and want to expand their program to the entire country. As it happens, in Sidney, Australia, they have been trying to organize an Earth Hour, to protest global warming. The idea is the same, turn off the electricity for one hour. The two groups have decided to join forces and the next Earth Hour will take place from 8 to 9 pm on March 29th. Even if only a few people make the effort to do this, it will make a big difference. I plan to be outside with my lights off on March 29th and hope for dark skies at least for one hour.

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