The Limb Of The Sun

Also, why do some flames look hollow? Thanks to http://www.audible.com/minutephysics for sponsoring this video.

More information about:

Limb darkening – https://en.wikipedia.org/wiki/Limb_darkening

Optical Depth – https://en.wikipedia.org/wiki/Optical_depth

Limb darkening – http://spiff.rit.edu/classes/phys440/lectures/limb/limb.html

Limb darkening and exoplanets – http://zuserver2.star.ucl.ac.uk/~idh/NewGrids/vLimb.pdf

Measuring the solar radius using limb darkening! – http://arxiv.org/pdf/1302.3469.pdf

Halo nebulas - http://blogs.discovermagazine.com/badastronomy/2010/12/16/a-delicately-violent-celestial-shell-game/

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