Size and Scale

http://astro.unl.edu/naap/motion3/animations/sunmotions.swf

On the size of things:

http://htwins.net/scale2/

http://scaleofuniverse.com/

http://xkcd.com/482/

http://xkcd.com/1331/
This is just cool.

http://workshop.chromeexperiments.com/stars/
















Jack Horkheimer (R.I.P.), for your interest.  Not related to the Celestial Sphere stuff.

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