Top Document: [sci.astro] General (Astronomy Frequently Asked Questions) (2/9) Previous Document: B.12 Is it O.K. to look at the Sun or solar eclipses using exposed film? CDs? Next Document: B.14 Why do eggs balance on the equinox? See reader questions & answers on this topic! - Help others by sharing your knowledge Author: Michael Dworetsky <mmd@star.ucl.ac.uk> The short answer is no (well, almost no). The long answer is given by David Hughes in the Quarterly Journal of the Royal Astron. Soc., 1983, vol. 24, pp 246-257. This mistaken notion was first mentioned by Aristotle and other ancient sources, and was widely assumed to be correct by many literary sources of the 19th century, and even believed by some astronomers. But every astronomer who has ever tested this by experiment came away convinced it was impossible. If you want to try an interesting experiment to see why it is believed that whatever people see up chimneys cannot be stars, try the experiment at night, as I have done, using a cardboard tube centre from a paper towel roll (mine had an opening of 25 square degrees). You will see that, at random, you will seldom include one visible star, rarely two, and virtually never more than two, in the field. Separate experiments to attempt to see Vega and Pollux through tall chimneys were performed by J. A. Hynek and A. N. Winsor. They were unable to detect the stars under near perfect conditions, even with binoculars. The daytime sky is simply too bright to allow us to see even the brightest stars (although Sirius can sometimes be glimpsed just after the Sun rises if you know exactly where to look.) Venus can be seen as a tiny white speck but again, you have to be looking exactly at the right spot. The most likely explanation for the old legend is that stray bits of rubbish get caught in the updraft and catch the sunlight as they emerge from the chimney. It is possible to see stars in the daytime with a good telescope, as long as it has been prefocused and can be accurately pointed at a target. User Contributions:Top Document: [sci.astro] General (Astronomy Frequently Asked Questions) (2/9) Previous Document: B.12 Is it O.K. to look at the Sun or solar eclipses using exposed film? CDs? Next Document: B.14 Why do eggs balance on the equinox? Part0 - Part1 - Part2 - Part3 - Part4 - Part5 - Part6 - Part7 - Part8 - Single Page [ Usenet FAQs | Web FAQs | Documents | RFC Index ] Send corrections/additions to the FAQ Maintainer: jlazio@patriot.net
Last Update March 27 2014 @ 02:11 PM
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