Miscellaneous
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Revision as of 23:11, 11 December 2007 by 18.251.6.42 (Talk)
Questions that really don't belong in any category, even a new one... Scales:
- What are the masses and radii of the following objects: electron, proton, earth, sun, solar system, globular cluster, open cluster, galaxy cluster.
- What is the spatial extent of the visible universe?
- If we go out at a clear night, how many stars can we see with naked eyes?