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.

How Many Sisters?

There is no better time for gazing at the heavens than in mid winter. Directly overhead, about 9 pm, are three bright star clusters and constellations: Orion, the Hyades, and the Pleiades. Part of the show are the super stars Sirius and Betelgeuse.

Orion the Hunter holds up his shield, warding off Taurus the Bull (containing the Hyades star cluster), who in turn defends the Seven Sisters of the Pleiades. Following close on Orion’s heels is Canis Major (Great Dog), whose bright nose is Sirius, the brightest star in our sky. Inset into Orion’s shoulder is giant red Betelgeuse. Each one of these objects is notable on its own. Together they are a light show that surpasses Las Vegas.

The Hyades is a group of a half dozen stars shaped like a V. It’s a true cluster—in that all of its stars are related. (In contrast, the stars of the Big Dipper, although they appear to be grouped, are disconnected and at vast distances from one another. They just appear to be aligned, from our vantage point.)

Orion contains some of the brightest stars in the northern hemisphere. His belt is three vivid blue stars that grab your eye. The shoulder star Betelgeuse is ancient; it's over 50,000 times brighter than our Sun and 500 times its size. If it were put where our Sun is, it would engulf the Earth and Mars.

Hanging from Orion’s dazzling belt is a sword of three stars. But the middle one is not a star; it’s the Orion Nebula—an immense cloud of interstellar gas, which is the blown-out leftovers of an ancient supernova. Today the clumps of gas are coalescing into new stars It’s a hot and active star nursery.

Yipping at Orion is Canis Major. The dog’s nose, Sirius, is the brightest star in our sky—24 times brighter than our Sun. Although Sirius appears to be an intense point of light to the naked eye, it is really a double (binary) star. Half the stars in our Milky Way are binary stars, but most can’t be separated with the naked eye. The Egyptians cast Sirius as one of their key stars. Its appearance each year heralded the flooding of the Nile.

Finally there’s the Pleiades. Pretty little Pleiades. It has a mystical, magical quality to it. It resembles a miniature teapot; sort of like a tiny Dipper. Its alternative name—the Seven Sisters—is Subaru in Japanese. Take a look at that car’s logo and get an idea of how the cluster appears.

When I look at the Pleiades I see six stars, not seven. So where does the name Seven Sisters come from? Greek mythology describes the seven daughters of Atlas being turned into stars by Zeus. So Pleiades got its label.

Some people have claimed seeing as many as 16 stars in the Pleiades cluster. I suspect it’s a little like a macho game of “Mine’s bigger than yours.” He who sees more stars is the winner. But there’s a way to beat all the braggers. Take up a pair of binoculars and you can see dozens of stars in Pleiades. Big telescopes register as many as 3000 young stars in the cluster—all a brilliant blue.

I can’t stand outside very long on mid winter nights, looking up at these stellar favorites of mine. The cold sinks too deep into my old bones. But I’m always stopped dead in my tracks by the sight of them, as I cross the yard. It’s delight that never tires.