Space Stuff
Finding Things in the Sky
copyright: David Carpenter 2001
Finding things in the sky requires some reference points. There are two ways. Either use the constellations or use coordinates. Generally, using the coordinates requires finding a reference star first. Either way, you have to be able to recognize at least a few stars.
Perhaps you have tried to use a star chart unsecessfully in the past. Which way do you hold it? Where is the horizon on the chart? If it's 3 inches on the chart, how big is it in the sky? Is it right side up? Maybe the star chart has lines (or worse, pictures) representing the constellations. When I look up at the stars, I don't see the lines.
Constellations originated because people tried to recognize otherwise random patterns of stars in the sky. Just as one person thinks a particular cloud resembles a boat, while their companion thinks the same cloud resembles a hat, people assign different meanings to star patterns. Ancient Babylonians saw a centaur (half horse, half man) where modern people see an "obvious" teapot. The swan has become a cross, and the rump of a bear has become the Big Dipper. I think Orion, when it rises in the east, looks like a celestial meter stick, and not so much like a hunter. And that's OK. As long as I can recognize the same star patterns, night after night.
There are 88 official constellations, and numerous other popular groupings of stars (such as the Summer Triangle). Some books confuse the beginner by trying to teach them all. I teach my students only three. That's all you really need to know. You can use the first few constellations you learn as a reference, then use a star chart to find the rest. The first three constellations to learn are the Big Dipper, Orion, and the Summer Triangle. Generally, two of these are above the horizon all the time. The Big Dipper never sets (as viewed from Ohio) and Orion is pretty much opposite the Summer Triangle. As one sets the other is rising.
Once you can identify these, you can find any star. All you have to do is use these stars as pointers and scales. If a star on a chart is two lengths of Orion and below Orion on the charts, it will be in the same place in the sky. Find these frequently, and before you know it, you will be recognizing other patterns. Some of the easiest second sets of constellations might include the "teapot" of Sagittarius, in the heart of the Milky Way, the "Great Square of Pegasus, and Cygnus (the Northern Cross) within the Summer Triangle. The two stars on the bowl of the Big Dipper, farthest from the handle, point upward toward Polaris, the North Star.
Don't be fooled. The North Star is not exceptionally bright. The brightest star in the sky is actually Sirius, to the left of Orion.
Once you recognize a few stars, it's time to look for some Fuzzy Stuff in Space. One of the easiest is the nebula that at a glance, appears to be the center star in Orion's "sword" [see the larger gray spot on the chart]. Another is found a couple lengths of Orion to the right. This "cloudy" patch of stars is the Pleiades, an open cluster. The star at the bottom of the Northern Cross is a pretty double star; a small blue star orbiting around a larger gold star [The colors are obvious even in a small telescope.]. With a little more experience, you'll use the Great Square of Pegasus to find Andromeda, then star hop to see the core of the nearest large galaxy outside our own [Don't expect to see any more than a big fuzzy blob though.].
The rest is just practice. Before long you'll be finding lots of neat stuff at which to aim a telescope, or a pair of binoculars.
copyright: David Carpenter 2001
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