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_darke...
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From this photo it’s easy to see that not all parts of a flame are made the same – theycan be brighter around the edges and darker in the middle. Which is weird, because a flameis normally *brightest* in the middle, since that’s where you’re looking at the mosthot burning gas.I mean,Look at the sun – actually, don’t do that without a solar filter – but, it’s abig ball of hot glowing gas, and it’s definitely brightest in the middle. In fact, not onlydoes it get darker towards the edges, it gets redder. These dark, red edges of the sun arecalled “limbs,” since “limbus” is latin for “edge”. And the limbs of thesun get darker and redder near the edge for three simple reasons:First, the sun is cooler closer to its “surface” and hotte...
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From this photo it’s easy to see that not all parts of a flame are made the same – theycan be brighter around the edges and darker in the middle. Which is weird, because a flameis normally *brightest* in the middle, since that’s where you’re looking at the mosthot burning gas.I mean,Look at the sun – actually, don’t do that without a solar filter – but, it’s abig ball of hot glowing gas, and it’s definitely brightest in the middle. In fact, not onlydoes it get darker towards the edges, it gets redder. These dark, red edges of the sun arecalled “limbs,” since “limbus” is latin for “edge”. And the limbs of thesun get darker and redder near the edge for three simple reasons:First, the sun is cooler closer to its “surface” and hotte...
