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Q & A: Where are we in the universe?

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Most recent answer: 01/01/2013
Q:
If the universe is expanding like a balloon, and we are in that balloon, can we determine our place in the universe by the measuring the relative velocity of other galaxies around us. For example, would not those galaxies between us and the center of the universe be receding slower relative to us than the other galaxies around us?
- Chuch Lype (age 18)
Beckley, WV, USA
A:
Remember that the balloon picture applies to an expanding 2-D space. In that picture only the surface of the balloon is real. So there is no center, all points on the surface are equivalent. If you paint dots on the balloon, each one gets farther and farther away from its neighbors on all sides equally.

We're in the 3-D analog, which our minds aren't properly equipped to picture. There's still no center.  As you look at far-away galaxies, they recede faster from us, just like dots on the expanding balloon.

Mike W.

(published on 01/01/2013)

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