1. We see a redshift in the spectral lines of distance galaxies, and greater redshift for more distant galaxies.
2. We can see distant galaxies dissolve, pulled apart by the expansion of space.
3. We can see the disks of galaxies getting smaller over time.
4. We see the edge of the universe moving away from us.
5. All of these responses are evidence that the Universe is expanding.
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From what evidence do we deduce that the Universe is expanding?