By Scott Mair
Photo by Charles Banville
It’s a crisp, clear night in Victoria, British Columbia. From the top of Observatory Hill the Milky Way streaks south across the sky towards Olympic National Park in Washington State. It’s like God has sprinkled a handful of diamonds against a black velvet night, as thousands of stars wink at me.
At moments like this, with star chart in hand, I used to try to figure out the constellations. Beyond the Big Dipper I was pretty much lost and I became convinced the Greek astronomers that named the constellations must have been heavy into the ouzo that night. I’m sorry: Ursa Major doesn’t look like a bear to me; it doesn’t matter how much my friend Don tries to describe where Boötes, the herdsman, is, I can’t make out its ice-cream cone shape; and Bernice’s Hair (Coma Berenices) may be a cool name for a constellation, but I can’t even see any stars in that part of the sky much less make out its shape.
Then I got a job running an astronomy interpretive center. There’s nothing like the fear of appearing stupid to focus the mind!
That’s when I discovered there are tricks to navigating the night sky. The first was: Find an anchor point. Most of the constellations might be unrecognizable, but a few are bright, distinctively shaped, and easy to find: the W shape of Cassiopeia, the distinctive belt of Orion, and the “big dipper” part of Ursa Major, for example.
The constellations that surround these anchor points may not be distinctive, but they always have at least one bright star. That is my second trick: Don’t worry about all the stars; just worry about the bright ones. If you follow the edge of the cup of the Big Dipper, the first bright star you come to is Polaris (the North Star), the brightest star in the Little Dipper, more properly known as Ursa Minor (the little bear). Once you have Polaris the rest of the Little Dipper is easy to pick out.
This photo of the Andromeda galaxy was taken by Charles Banville, an amateur photographer in Victoria, British Columbia.
Follow Orion’s belt up and the first bright star is Aldebaran, the brightest star in Taurus, the bull. Before you know it you’ve tracked your way from one constellation to the other right across the sky and your life will never be the same again!
Once you know the constellations you will always look up at the night sky. It won’t be a casual look like the “old you” used to make. You’ll make a point of seeing who’s up in the sky tonight. And the more you look, the more you’ll see.
You’ll begin to notice that the stars scroll across the sky each night, a telltale sign that the planet you’re standing on does indeed rotate. When you look through a telescope eyepiece and the object you are viewing tracks across the field of view, it’s not the object moving, you’re actually seeing the effect of the rotation of the earth.
As the constellations change with the seasons you’ll be able to visualize the orbit of the earth around the sun as we look into a new patch of outer space each night.
You’ll notice that the sun, the moon, and the planets don’t track randomly across the sky, they all follow the same path—the plane of our solar system—and that the Milky Way marks the plane of our galaxy.
When you notice that Venus and Mercury go through phases like the moon, but Mars, Jupiter, and Saturn don’t, you’ll grasp where our orbit fits into the solar system. Planets between the earth and the sun go through phases. Planets beyond our orbit don’t. If you were magically transported to a new solar system you could easily figure out where your new planet fit into its solar system.
When you can navigate the night sky and understand why it moves the way it does, your understanding of your physical place in the universe is no longer an amorphous, academic concept. Where you are on the earth, where the earth is in the solar system, what part of the galaxy we’re in, and who our neighbors are in this corner of the universe will become tangible and concrete. It’s a really cool feeling.
On that frosty night in Victoria, I want the people lining up to look through my telescope to begin to get that feeling, to grasp the wonder and beauty of the cosmos.
If we’re looking at the moon or Saturn, astronomy interpretation is easy. With those objects the resource speaks for itself. Sometimes I don’t even say anything. When the person looking through my telescope asks, “What are we looking at?” I just say, “You tell me.”
With the moon the response is immediate: Wow, cool, amazing! Or they don’t say anything, struck dumb by the beauty of it all.
With Saturn it sometimes takes them a while. “Well, it’s…. It’s…. Oh, oh, oh! It’s the one with the rings! It looks just like the picture.” And then they say, wow, cool, or amazing, or they’re struck dumb by the beauty of it all.
For most of the “deep-sky objects” I show the public (nebulae, galaxy, star clusters) it’s not quite so easy. The problem is they expect to see a Hubble Space Telescope picture and get a humble Scott telescope image instead. For me and my fellow amateur astronomers, doing “public outreach” (as the astronomy community calls interpretation) will be all about managing disappointment.
Luckily, I’m an interpreter! I know all about linking the tangible and the intangible. Freeman Tilden is my best friend and the social contract model of interpretation is tattooed on my rump.
I hope it helps because I’m going to try to convince the person looking through my telescope that the Andromeda galaxy (M31), the gray smudge they can barely see in the eyepiece, really is a galaxy with billions and billions of stars, millions and millions of light years away.
Before I even start though, I remember that I’m not just talking to the person looking through my telescope; I’m also talking to everyone in line. It’s never fun waiting, so I make my stories big and entertaining to reach them, too.
Although the stories I tell will vary with each person (I try to tailor my talk based on their questions or conversations I overhear), I prepare everyone for what they are going to see before they look through the eyepiece. I tell them they are going to be looking at an island universe of more that 500 billion stars, as much as a light-year across. I want their brains to fill in what their eyes can’t see. It’s not a gray smudge; it’s an island universe!
While they are looking I want them to appreciate how special this moment is. The light that is reaching their eyes right now started on its journey 2.5 million years ago—before there were even human beings on the earth. Ninety years ago we didn’t even know that other galaxies existed. They use to be called spiral nebulae (nebula is the Greek word for cloud) until Edwin Hubble was able to resolve individual stars in Andromeda with the 100-inch Hooker Telescope in California.
I want to tie them to the place we are observing from. Observatory Hill gets its name from the 72-inch Plaskett Telescope that towers above us. It was built in the same year as the Hooker. Even though the Hooker Telescope was finished first, the Plaskett’s design was so good it was up and running immediately, doing science for six months before the Hooker was completely operational. For six months, the Plaskett was the largest operating telescope in the world. (Hey, I’m Canadian—I take my glory where I can.)
I want to tie the cosmos to popular culture, too. The Milky Way is gravitationally tied to Andromeda. We’re part of a little gang of galaxies that travel through space gravitationally tied together. We have a really cool gang name—The Local Group. Wouldn’t that look good on the back of a jacket?
I also want to tie their own bodies to the observing experience. I remind them they will get a better view of Andromeda if they don’t look directly at it. Astronomers call this averted vision and it works because of the anatomy of our eyes. We have two kind of light receptors in our eyes: cones for color vision that require bright light to work and rods for low light that give us black and white vision. The cones are concentrated in the center of our eye. If we look directly at Andromeda the image falls on the cones, but there is so little light reaching our eyes from the galaxy it’s not enough to cause the cones to fire. If we look slightly off to the side the image falls on the rods, which can fire in low light. A black-and-white image is better than no image at all.
Most of all, I want them to have fun. I want them to have so much fun, they will want to do this again and again and again. I want them to know you don’t have to be a math genius, that telescopes are easy to use, and that astronomers may be kind of geeky, but they’re nice, too. I want them to know there is a wonderful show above our heads every night. They just have to tilt their heads back and enjoy.
Scott Mair came to Victoria, BC, as the founding director of the Centre of the Universe (how’s that for a job title?). He still does astronomy programming at the Swan Lake Nature Sanctuary, where he is the program manager.
