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I'm pretty sure we get orders of magnitude more illumination from the sun, even in the middle of the night, than we get from any other star.
by cperciva 10y ago
I'm pretty sure we get orders of magnitude more illumination from the sun, even in the middle of the night, than we get from any other star.
- kurthr 10y agoIt's called moonshine :^) at a magnitude of -14, the moon, which has ~0.25% of the brightness of the sun at -26. All of the visible stars in the sky come to less than 10% of the moon's illumination. https://en.wikipedia.org/wiki/Apparent_magnitude https://en.wikipedia.org/wiki/Apparent_magnitude
- thaumasiotes 10y agoSure, we get more illumination from the sun at night than we do from the stars. That doesn't mean we can see the sun at night; we can't.
- cperciva 10y agoCan you see the sun through a (reflecting) telescope? What's the difference between seeing a star via its light reflecting off a planet and seeing the star via its light reflecting off a mirror?
- thaumasiotes 10y agoMirrors show the image of what they reflect. Non-reflective surfaces don't. What's the difference between the image of yourself in a puddle of rain on the sidewalk, and the image of yourself in the dry concrete of the sidewalk? One exists, and one doesn't. There's still light that travels from you, to the sidewalk, to your retinas, but that light reveals essentially nothing about you. The sidewalk has overwritten the information it used to carry.
- cperciva 10y agoI was thinking even when the moon was on the wrong side. IIRC we get more sunlight reflected off Jupiter alone than we get from any other star.
- nkrisc 10y agoSure but you can't see the sun at night...