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Yet another example of why I left Indiana

A Geocentrism conference? Really?I saw this story floating around and wasn’t going to comment on it, but then I found out the conference is being held in South Bend, Indiana. Oh, Indiana. This is why I usually tell people I’m from Chicago instead (my home town is a Chicago suburb in Indiana, I swear!).

Phil Plait has an excellent summary of why Geocentrism is wrong over at Bad Astronomy, including this particularly insightful bit:

Look, I’m human: I say “The Sun rose in the east today”, and not “the rotation of the Earth relative to the rest of the Universe carried me around to a geometric vantage point where the horizon as seen from my location dropped below the Sun’s apparent position in space.” To us, sitting here on the surface of a planet, geocentrism is a perfectly valid frame of reference. Heck, astronomers use it all the time to point our telescopes. We map the sky using a projected latitude and longitude, and we talk about things rising and setting. That’s not only natural, but a very easy way to do those sorts of things. In that case, thinking geocentrically makes sense.

However, as soon as you want to send a space probe to another planet, geocentrism becomes cumbersome. In that case, it’s far easier to use the Sun as the center of the Universe and measure the rotating and revolving Earth as just another planet. The math works out better, and in fact it makes more common sense.

However, this frame of reference, called heliocentrism, still is not the best frame for everything. Astronomers who study other galaxies use a galactic coordinate system based on our Milky Way galaxy, and the Sun is just another star inside it. Call it galactocentrism, if you want, and it’s just as useful as geo– or heliocentrism in its limited way. And none of those systems work if I want to know turn-by-turn directions while driving; in that case I use a carcentric system (specifically a Volvocentric one).

You use coordinate systems depending on what you need.

So really, there is no one true center to anything. I suppose you could say the Universe is polycentric, or more realistically acentric. You picks your frame of reference and you takes your chances.

…That’s where Geocentrism trips up. Note the upper case G there; I use that to distinguish it from little-g geocentrism, which is just another frame of reference among many. Capital-G Geocentrism is the belief that geocentrism is the only frame, the real one.

I never thought about it that way! Thanks, Phil!

Seattle meet up this Sunday! » « Oh no, they already know I’m here!

Comments

  2. Livingonsteak says

    Wait, what?I almost wish I was back in South Bend just so I could go laugh at them.It’s being hosted by Notre Dame, isn’t it.Also, it would appear that we broke their site by going over their bandwidth limit.Tip for hosting websites with controversial stuff on them: Don’t have a bandwidth limit.

  3. Rosen says

    It’s not only about convenience. Systems of massive bodies in the space turn around each other keeping a steady* common center of gravity. Being the Sun much more massive than the planets, the Solar System’s CoG is inside the Sun, but binary stars rotate together around a CoG placed somewhere in the line that connects them.*steady, unless the system itself is rotating around another system.

  9. Old Earth Accretionist says

    I was more floored by their claim to have “scientific” evidence! Although why history is being used as support for “scientific” claims I also have no idea….O.o

  15. mihoda says

    When it comes down to it one can come up with the equations for an earth that is stationary and center of our universe. It’s based very simply on Mach’s hundred plus year old principle of relativity. Medieval descriptions of the planets moving in loopy orbits around the earth, perfectly accurate from the heliocentric perspective once you transform the equations into a heliocentric frame.However, the assumption of the cosmological principle is likely a good one and has led to some amazing (confirmed) predictions about our universe. So the idea that the earth is the center of the universe(as opposed to say, just the OBSERVERED universe) are simply false. They fall down in the face of confirmed theory.

  17. says

    I’ve actually been to Southbend. Well the airport actually. We were supposed to land in Chicago to catch a connecting flight to Phoenix, but the Chicago airport was closed because of “weather”. That’s in quotes because I have no idea what kind of weather could be bad enough to close an airport in the middle of June (we missed our connection twice and it turned into the longest night of my life, did I mention we were travelling with two preschoolers?). Anyway I found the airport fairly unimpressive, but now that I know that Southbend Indiana is actually the centre of the universe…well.

  18. Angela says

    Actually, historical evidence for geocentrism makes sense, just not in the way they mean. It’s perfectly legitimate to study why past societies thought the Sun revolved around the Earth. In this case, “historical evidence” means “the evidence used by people in history” rather than the erroneous “evidence from history used to prove a point now.”Just had to play devil’s advocate. :)

  19. says

    Some theories I’ve read actually have pointed out the probability that the entire universe rotates. Like a giant rotating wheel, with billions of rotating wheels, that, are also covered in billions of rotating wheels, and so on, and so forth, etc., etc., ad infinitum.

  21. NotThatGreg says

    I’d especially be interested in “Scientific Experiments Showing Earth Motionless in Space”. (cos, I’ve been doing scientific experiments measuring the surface of the lake this summer, and near as I can reckon it’s *flat*, not curved. Can’t get the canoe to go downhill *anywhere*).

  22. says

    I love the way Phil described how geocentrism fits into our way of looking at things, I never thought of it that way.I totally get what you mean about Indiana, I grew up in Illinois but lived thisclose to the border. It’s like a different country sometimes.

  24. NotThatGreg says

    Arrggg…. to all those folks who think science is so badly wrong: why don’t you go build your own internet according to faith-based principles (maybe there’s something in Ezekiel or Leviticus which describes packet routing schemes, and forward-error-correction). No using satellites of course. Probably you should find something acceptable to replace all semiconductors, since I’m pretty sure quantum theory is blasphemous too. Let us know how it works out. Meanwhile stop filling this one up with your drivel.

  25. ckitching says

    I suppose they could use Einstein’s theories on relativity. Fortunately, they associate that with moral relativism, so they’re vigorously opposed to it, too.

  27. Rollingforest says

    It was actually understandable why people in the 17th century believed in geocentrism. Many scientists made the point that if the Earth really was moving, wouldn’t we feel it? When birds flew in the air, they would be left behind as the Earth flew onward. The scientists of the time didn’t understand gravity or inertia as we do now.

  31. luke says

    Say what you will about the Ptolemaic system, but it is undeniably in its own way a monument to human ingenuity.

  35. Pratchettgaiman says

    I thought this kind of thing was pretty much settled once we launched probes into space that took pictures of the Earth moving around the Sun, but I guess not….I’m still holding out that the Earth is supported on the backs of 4 elephants who in turn stand on the back of a turtle. And yes, I am a nerd and so are you if you get the reference.

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