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    Re: Venus in daylight
    From: Frank Reed
    Date: 2020 Mar 31, 22:23 -0700

    Two things will work against seeing Venus from your southern latitude. Low altitude means higher atmospheric "extinction" which means Venus is fainter, and it also means that the sky background is a lighter shade of blue, washed by haze, so less contrast. But remember this: the surface brightness (which can be counted in magnitudes per square minute of arc) of the Moon's brightest highland features is five times or more lower than the surface brightness of Venus. But you can see the Moon, right? Therfore, Venus is there, too! 

    It's hard to believe until you've done this a dozen times yourself and showed it to a few dozen incredulous non-astronomers. Venus, as it approaches and passes through this period of "maximum brilliance," is really shockingly, obviously bright once you finally lay eyes on it. And that's the tough part. Our eyes have great difficulty sitting still on a white dot on a light blue background. But once you've seen it and "walked it" to a convenient foreground object, like a tree limb, that you can return to easily, it's truly amazing how easy it is to find it again. Venus is bright and easy in daylight --as soon as you've found it once. 

    By the way, when I was looking at it today in mid-afternoon, only 20° from the zenith, I had to laugh at my discomfort. As I noted in an earlier message, when you see a star or any celestial body that high, it feels like you're looking straight up. And it's an actual pain-in-the-neck. Your problem, that Venus is so low that contrast in low-altitude haze is working against you, compared to my problem, that Venus is so high in the sky it makes my neck ache, strongly suggest that we are on opposite sides of a great sphere. I think it may be true after all. The Earth is round!

    Frank Reed

       
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