|MadSci Network: Astronomy|
My friend said that he can read a map in nothing but starlight. He makes stuff up all the time, so I have doubts, but it makes sense that he could just have good eyes. He came back from a camping trip and said he'd done it. I can think of three ways he's telling the truth: 1. He really does have better vision than most people. 2. The moon was out (I think it was close to the sun, on the day-side of Earth) 3. The lights from the nearby city gave him extra light. Does number 3 make sense? - The city is Tucson, AZ. I don't how they measure light pollution, so I can't tell you how bright it is (thought you might know somebody from a telescope down here that could tell you). - He would have been about 5,000 feet above the city, and 5-10 miles north of the city. - He was in a valley between a couple of the lower "peaks", with one of them directly between him and the city. - My thinking is that the light from the city, while not directly visible, went up into the atmosphere, then bounced around until some of it came back down, providing a significant amount of illumination. He's not objective about anything (he attempts to refuse to be proved wrong), so I wouldn't be surprised if there was obvious light pollution that he didn't notice. Thanks, R. Michael Starr II, A1C, USAF
Re: How much light would a city add to starlight, for reading by starlight?
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