(Dis)Orientation: 2. Guidelines
Part two of an astronomer's notes on finding our way. In this section we put pinstripes on Santa to understand our place on earth and in space.
Author’s note: this is a revised and improved version of the second section of a six part series on getting oriented in the sky, and in life. This section expands on concepts presented in the first section, so if you haven’t read it, I recommend reading that first. After reading this section, here are the links to the third, fourth, fifth, and sixth essays in the series if you’re interested. The original version of the series was titled “Lost in Space.” You can find the older original version of this post here.
[Latitude and Longitude - an imaginary net to keep Earth from falling. Images from Michael Richmond. ]
Section 2: Guidelines
Constellations are one way we can get a sense of place among the stars. But they are big and bulky – covering large areas of the sky. Just like you need more than just the correct state to get to your aunt’s house, pointing telescopes at specific objects requires something more precise. So here’s another, more exact way of getting oriented: coordinates. Bear with me now, it’s not as scary (or dry) as you think. Coordinates just assign each spot a couple of numbers that tell you its exact location. On earth we call these numbers latitude and longitude, and they show up when you drop a random pin on Google maps.
How exactly do we choose these numbers? Well, they’re defined relative to the spin of the earth: earth spins on an axis that goes through the north and south poles, and the equator is the big circle halfway between them, dividing the earth into a top and bottom half. We also split the world in half vertically (like slicing an onion through it’s hairy head of roots down to it’s pointed tip) - and call the cut the prime meridian on one side of the world, and the international date line on the other (The prime meridian goes through Greenwich, England, because a group of powerful people in 1884 decided it would - I mean, you had to choose somewhere, and apparently 72% of the world used British navigation maps in 1884). This giant slice forms a circle from the north pole down to the south pole and back again.
For some reason folks in ancient Babylon decided that there are 360 degrees in a circle, (and thus 180 degrees in a half circle and 90 degrees in a quarter circle), and traditions, once established, rarely change. So latitude ends up being a number between 0 and 90 that tells you how far north or south of the equator you are (90 degrees South at the south pole, 0 at the equator, and 41.9572 degrees North here by the rackety radiator in the back room at Dollop Coffee Shop in Chicago (just a little less than halfway to the north pole from the equator). And longitude is a number between 0 and 180 that tells you how far east or west you are of the prime meridian (87.6498 degrees W here at Dollop, since I know you were wondering).
If you’re struggling to picture it, imagine the earth as the great belly of a round Santa wearing a pin striped suite. Call the vertical stripe going through his buttons 0 degrees, and then count stripes going to your left (west) and right (east). If you could actually fit 360 stripes around the shirt (a bad idea, but let’s face it, imagining Santa in pin stripes is already a bad idea), in Chicago I’d be 88 stripes left of the center.
[The Astronomer’s imaginary coordinate grid. Images from Michael Richmond. ]
Astronomers create a similar grid on the sky. They imagine all the stars and galaxies as little stickers located on the inner surface of a large imaginary sphere with the earth hovering in the middle of it, like a nucleus in some spherical glass atom. The north star (Polaris) is a sticker located directly above the Earth’s north pole. Astronomers call this point the “celestial north pole.” They similarly take the place directly above the south pole to be the “celestial south pole,” and the ring directly above the equator, halfway between these celestial poles the “celestial equator.” With these mappings they are able to define a sort of “celestial latitude and longitude” to locate stars and other objects in the sky. The official names for these are Right Ascension (which is just celestial longitude, abbreviated RA) and Declination (celestial latitude, abbreviated Dec). So now you can impress your friends at parties. Just like the radiator at Dollop Coffee Uptown is at 41.9572 N, 87.6498 W, the star Betelgeuse (Orion’s armpit - literally translated “armpit of the mighty one”) is stuck on the imaginary sphere at 7.4 degrees N, 88.8 E. This fixed position on the map relative to all the other stars and objects is really great for pointing telescopes, since it can be as exact as necessary, and doesn’t change throughout the year. It’s fixed at that spot. (Well, mostly… Betelgeuse is technically moving through space. We call this it’s proper motion - its motion relative to the coordinate system. But for the vast majority of astronomical objects, this motion, while it might be really fast in actuality, appears tiny/ indetectable on the sky, since objects are so far away. For example, even though Betelgeuse is moving at 67,000 miles per hour, it would take over 71,000 years for its RA to change by even half a degree).
If this whole discussion of getting oriented has you feeling more lost than before, you’re not alone. Thinking about coordinate systems is pretty mind bending. Part of the difficulty, as you’ve probably gathered, is that so much of it seems somewhat arbitrary, like it’s made up. And the issue is, it is. What we are essentially doing is putting down a bunch of curved rulers on the earth, to measure distances relative to some reference spot. But you have to choose a place to measure distances from, and you have to choose how to position the rulers (up, down, tilted at 37 degrees?), and you have to choose what sort of marks you want to put on your ruler (millimeters? inches?). (For the sky we chose Greenwich and the North Pole, tilted to align with the spin of earth’s axis, and degrees).
I read on the internet once that René Descartes first came up with modern coordinate systems watching a fly on his ceiling above his bed, and wondering how to describe its exact location. Don’t believe everything you read on the internet. But do think about pinning that fly down - it’s a helpful mind game. You’d want to pick a reference, say the corner of the room near your head and to the left looking up. You’d need to then define an orientation for your rulers - the directions of the walls, and a way to quantify distances - maybe by comparing to the size of a ceiling tile, or a poster of Santa in his pinstripes.
I find it somewhat telling that we invent invisible lines to tell us where we are. How do you find a galaxy? Use these RA/Dec lines. How do we find ourselves? Well, maybe that’s harder. But it seems to me there still are lines. Obvious lines like yellow police caution tape that keeps you moving on the sidewalk, or double yellow lines on asphalt that keep you moving in your lane. And more subtile lines like the looks that make you move to the back of the incredibly straight queue to board the London Underground (British culture, in my experience, incorporates an impressive ability to wait in line; New York subways have no such constraints). Or consider other lines constructed less intentionally, but powerful guides nonetheless. Like my friend Ben, frustrated at the pressure generating power of well-meaning, but thoughtless comments leveled by grandparents and strangers alike at his kid: “They say things like `he’s so good at that puzzle, he’ll be an engineer!’ of `He likes that music so much, he’ll be a world class musician someday!’ How do they have any idea? The kid’s 4! But he hears them.” Or my own experience, my uncle, the teacher, long before I even knew what a PhD was, just because he knew I was, as they say, smart: “Here comes the professor now!” Oh how those words warmed me. I wanted that. I wanted to make him proud.
Once constructed, these lines, for better or worse, direct our thinking like railings along a path. I see the north pole as the top of the world, and think of moving north as moving up, and east as sideways. Our city streets align to these cardinal directions: those that don’t we call angled, or weird. This is just obviously the way things are, I’d think, if I were ever even forced to ponder it. To consider those maps that made the south pole the “top” (and many excellent southern hemisphere map makers do), is weird, and even more out there ideas, like choosing a top in say Ecuador, or Kenya – that’s just confusing.
I find it interesting that being lost is a relative phenomenon - I’d be as lost in your hometown as you’d be in mine. Because really, my life coordinate system is relative to some home. That is, to turkey dinners, and the piano, and laughter, and the one place that fear can take a small leave because someone else was in charge.
As a kid I loved coloring books, and that box of 64 color crayons with that burnt sienna dirt brown and cerulean water blue. I love that cerulean blue. As it would get worn down, you’d have to unpeel a bit of that paper wrapper and sharpen it in that little white plastic hole in the back of the box. I think it broke once in a fight with one of my siblings. I was proud of my ability to stay within the lines, coloring in little circles like my mom, the artist, the painter, taught me. My Mickey and Donald didn’t look quite as nice as the Minnie she’d colored, but I was still pretty proud. My sister, young at the time, would scribble all over the page. It’s funny how coloring between the lines is a learned habit. We have to will our brains and fingers like sailors trying to control a docking ship.
Sometimes, I think, we wish these lines weren’t there. After all, they represent constraints, clear directions to instruct our advancement. As an oldest child, I tended to be a rule follower. Whether or not something was “allowed” colored my feelings about an activity, even when I didn’t want it to. Like eating food on the train: it was great, until I learned it wasn’t allowed. Or, you know, my favorite color was pink - any and all pinks: I loved their bright hues and the way they stood out, and surprised. But I was teased about it, and with some indirect encouragement from my mom, I changed it to red, a better color for a 90s boy.
So we see there’s an underbelly to these stripes, an invisible net we weave to ensnare the world. But we also see, perhaps, that as it is made, it might be unmade, or at least patched, or changed. A little disobedience, a little toeing the line, even perhaps crossing it now and then, can be freeing. We certainly celebrate the “right kind” of deviance. Fahrenheit 451 starts with a quote from Juan Ramón Jiménez: “If they give you ruled paper, write the other way.” And I mean, how else might we make progress?
Yet, even deviance has its limits, every construct has its rules. Without lines to follow, the curves of Mickey’s ears, how do we learn to draw at least something that can be recognize by someone else? So sometimes, I guess, I’m thankful for the lines. I remember growing up our church did a study called “Freedom in Christ.” It was my Pastor Dave then, I think, that first introduced me to the idea of freedom through constraint. By giving up some of our freedoms or priorities to something greater – in this case the rein of God, invisible, but present – we could actually find a more true freedom – say freedom from the bonds of our own desires, or the ropes of societal expectation. I’m sure that to many people, and perhaps to me at several points in my life, this sounded like religious brainwashing. But I think now that he’s at least in part, right. To be free, really free, does require constraints. My wife and I share more freely in the constraint of our promises to each other, I can drive faster to my destination because we all, mostly, submit to the rules of the road. In the words of renown marathon runner Eliud Kipchoge, “Only the disciplined ones in life are free.”
What I’m working toward, I suppose, is this: that like it or not, my experience is we use a set of shared invisible lines to orient our thinking and find our way. And it is relative to these bearing that we can sometimes find ourselves lost. Which, I think, is important. Consider, what does it mean to be lost? From Webster’s new world dictionary: “6. Having wandered from the way; uncertain as to one’s location.” Of course, we use the same word for ruined, damned, not winning, wasted, misplaced. No wonder we are wary of wandering too far from whatever is “the way.” Wayfinding, then, is an exercise in coordinate identification: determining where we stand and how to think and move in reference to shared constructs of invisible lines.