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I was hoping that astronomy enthusiasts/scientists would help me out with a simple question about light. Hold your outstretched hand up to any bright light source (the sun, or even a light bulb) so that the light is completely blocked by at least one finger, and then slowly move your finger to the side until the light just peeks around. There seems to be a glow when you do this, and I was wondering what causes this.

Is the light bending around my finger from some sort of diffraction? What's going on?

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closed as off-topic by Gerald, Robert Cartaino Feb 23 '14 at 19:15

  • This question does not appear to be about astronomy, within the scope defined in the help center.
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That's by [refraction][1] and [light scattering][2]. [Diffraction][3] occurs, but is too weak to be noticeable. [1]: [2]: [3]: – Gerald Feb 22 '14 at 20:22
This question appears to be off-topic because it is about physics. – Gerald Feb 22 '14 at 20:26

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