Title Bar - Cosmology
Activity: Building the Expansion

While the previous example is a good beginning for imagining a stretching universe, it is only two dimensional and does not clarify the idea that all points are expanding simultaneously. A good and simple way to demonstrate that the universe expands from all points simultaneously and has no real center is to print out the pictures found here footnote29 onto transparencies for use on an overhead projector or put one on regular paper for individual use.

These images of points which represent galaxies, when overlapped on a certain "galaxy" show expansion from that point but when overlapped on another "galaxy" seem to center around the new point. Thus no matter where in space the expansion is viewed, it appears that everything is moving away from that point footnote31.

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