Saturday, December 10, 2016

Searching for Andromeda

When you walk outdoors on any clear night and gaze upwards, you may see 2-3 thousand stars, if you're away from interfering city lights. Every single star you spot resides in our Milky Way Galaxy. There are a few hundred billion stars out there in our home galaxy, though you'll see, naked eye, at most a couple of thousand. Get yourself a pretty decent telescope and you'll maybe see a few tens of thousands of Milky Way stars, but that's still just a very small fraction of the total.
There's another quite different kind of astronomical object than stars in our home galaxy to look for: Andromeda Galaxy. It's much farther away than any star within our galaxy, but it can still be observed, because it's so huge. Due to its distance, however, we can't distinguish with the naked eye any of Andromeda's individual stars. All we see is a milky smudge.
The other night my neighbor came by for a two-person star party. He brought the beer, I set up my telescope, and we set out to view the heavens. As our solar system planets are currently not visible overhead in this November's night sky, Andromeda was our best celestial object for the evening, so we set up to view it.
Andromeda is not an easy thing to locate... at least for me. That's why I bought a very nice telescope a couple of decades ago. It comes with a small but amazingly capable computer that both steers the telescope to celestial objects and then locks onto them, following them across the night sky, as the Earth rotates. It's a wonderful little tool; align the scope to the North Star and another prominent star, and you've calibrated it for the night. Now all you do is type in the name of one of several thousand celestial delights in the tiny device and the scope will slew itself around, to stop and aim itself at the object you chose.
Unfortunately, the problem for an old analog guy like me, when trying to operate one of these digital wonders, is that I can't always understand the instructions. The directions confuse me and my thumbs are just a little too slow and clumsy, and I screw it up. I know if I had a 12-year-old computer nerd with me, he'd have the whole thing nailed in five minutes.
Unable to perform the alignment procedure accurately enough to have the little computer locate any celestial choice of mine, I must do it manually. So when my neighbor arrived he and I partnered, in an analog attempt to find Andromeda. I had been successful a couple of nights earlier (after an hour or so of effort) so I knew it could be done.
Despite our diligent attempts, we failed. I thought at one point that we were zeroing in, but alas, we saw no Andromeda. No big smudge; just more stars. Maybe the beers were impeding our astronomical skills. Whatever the limitation, Andromeda was not to be found that night.
What we did discover, however, was a phenomenon that every night sky observer comes upon, if you spend more than 15 minutes looking up on a clear, dark night: there are so many other things to see. Over the next couple of hours we gazed at the Pleiades, the Hyades, and then we dove into the core of our Milky Way Galaxy, where you can see so many stars that they blend into, well, a milky trail across the sky. The only thing that terminated our evening was the November chill penetrating into our bones, and opening the last two beers.



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