My wife noticed, many years ago, that every time I walk outside at night, the first thing I do is to look up. For a while she assumed that it was because I had a telescope operating somewhere and I wanted to see the condition of the sky, the locations of the clouds. Then she realized that I would even do it when she knew that I wasn’t using any telescope anywhere. It’s just what I always did: walked outside, looked up. Finally, she asked me about it. My first reaction was: I do? But then, after awhile, I realized: I do. I am always curious about clouds and about clarity, but mostly I just want to make sure that everything is right with the universe, that all of the stars are in place, that the moon has moved to whichever new spot in the sky it should be that night, that any of the planets that might be up are where they are supposed to be.
Sometimes I get a bit of a jolt, even though I know it is coming. When I fly to Hawaii and go use the telescopes out there I look up at night and see, oddly, that Orion is almost straight overhead, instead of low in the south like it is supposed to be. At that point my eye always travels north to try to find Polaris, now dangerously close to the horizon. Then I take a glance as far to the southern horizon as possible and I see something unsettling: stars I don’t know. I might as well be in another universe.
For all of my traveling the globe to go to telescopes, I’ve only been south of the equator once, for my honeymoon. When I went outside and looked up there, it was an odd combination of familiar and bizarre. In the north, Orion was flying overhead, but upside down. The bright red Betelgeuse, which translates as armpit of the giant, should really be called kneecap of the giant from there. The moon was also much further north than I was prepared for and it, too, was upside down. It really did give me that feeling that I was standing on the opposite side of the world, that my head really was pointing in a different direction than when I was at home.
One of the reasons that I was surprised when my wife mentioned to me that I always look up is because I was a little surprised that everyone else doesn’t do the same thing. The grand vista of the stars and the planets is above us night after night, and all you have to do is to look up. Most people are shocked when you explain to them, for example, that you can look at Betelgeuse and you can look at Sirius, and you can see that they are different colors. They’re amazed to know that that bright light in the twilight sky is not an airplane but is indeed the planet Venus. They are truly floored when you suggest to them that they get out a pair of binoculars and look at Saturn – high over head in the sky these days and you can see the rings. Or the moons of Jupiter. All of the stuff is out there for the taking.
I was in New York City this past week to give a lecture at Sarah Lawrence College. To get to Sarah Lawrence I walked my way down to Grand Central Station in the late afternoon, stared at the board of departures trying to figure out which was the right train to take, bought my ticket at an automated dispenser, and then had a few extra minutes to kill before the train left, so I stepped back against a wall to watch the people go by. Everyone was in a hurry across the floor, trying to catch a train or make their way home. But somebody on the other side of the concourse was doing something that no one else was doing, so it caught my eye. She was looking up. Curious what might be attracting her attention, I did the same, and there, inside of the building, a hundred feet up on a huge dome ceiling, was the sky.
Not just any sky, a spectacular painted sky with stars in place but also the constellations drawn and the ecliptic and celestial equator drawn through! Orion (with a gleaming Betelgeuse in his armpit) battles Taurus the Bull in the heart of the flowing Milky Way while winged Pegasus watched high above. Castor and Pollux look, to me, like they are plotting mischief to the side.
And, with thousands of people streaming through the concourse, there was one – now two – people actually looking up to notice. It reminded me of, well, of Los Angeles at night, where no one bothers to look up.
Because the constellations were painted along with the stars, I concentrated on the constellations. They were what was new to me. When I look at the real sky, I look at the stars, and don’t think much of the constellations, since no one has taken the time to paint them in the sky. But here they were beautifully drawn with sparkling stars as highlights.
Something was a little funny, though. At first, since I was concentrating on those new drawings, instead of on the real stars, I didn’t quite get it. But then it hit me: Taurus is on the wrong side of Orion. Castor and Pollux are switched. And what is Pegasus doing high to the left instead of to the right? It was like the real sky, only backwards.
Backwards is not the same as upside down. Backwards is like a mirror. Backwards it like you never ever really see it anywhere on earth, or, really, anywhere else in the Universe.
My scientific, educational self was offended. What? They spend all of this effort to put the sky on the ceiling and they get it wrong?
The ceiling, though, was copied from artwork that was supposed to be illustrating what the sky looks like from outside the Celestial Sphere. Except for one thing: there is no such thing as a Celestial Sphere. The Celestial Sphere is what you would think was out there if you considered the whole night sky to be a planetarium with little points of light a small distance away. Imagine now that you can sit outside the planetarium and see the stars. This is what the ceiling at Grand Central looks like.
And then I went from slightly offended by the inaccuracy, to thoroughly charmed by the historical accuracy. Yeah, I thought. People really used to think that you could step outside and look in and this is what they would see. This ceiling is fantastic.
It is the International Year of Astronomy.
A few weeks ago I participated in a panel discussion with 4 other astronomers as part of the celebration of the Internation Year. The event was sponsored by, among others, Discover Magazine. In this month’s issue they have a [heavily edited] transcript of the discussion amongst the five of us from the event. I am proud to say that, in the [heavily edited] transcript, I got the last word from the night, based on a question from the audience. Discover Magazine gets the last word:
Audience: What are your hopes for this year’s International Year of Astronomy
Brown: If there is anything I can convince people to do, I want people to not just sit here and listen to astronomers and think about astronomy but to look at the sky. So what I want everyone to do where you walk out tonight is to look up. You’ll see Orion, you’ll see Sirius. Just look up at the sky for a minute and think about what’s out there. That’s what I want.