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Re: Faint stars easier to find on the horizon first?
From: Trevor Kenchington
Date: 2004 May 28, 08:55 +0000
From: Trevor Kenchington
Date: 2004 May 28, 08:55 +0000
Doug Royer, extending standard technique from faint stars to the brightest of planets, wrote: > Try this trick also on Venus as one may view Venus in early C.T. when > conditions are right. If you know just where to look, Venus can be visible to the naked eye in full daylight. I have only tried finding it the once but, that time, I did find it. Needed some concentration to keep it in sight though, since you have to look in exactly the right place or it disappears. (Maybe it needs the higher resolution of your retina's fovea to be able to distinguish the small patch of brighter light from the general brightness of a blue sky.) Why can't we use Venus to get a day-time position line? I'm guessing that a sextant telescope doesn't help because its light-gathering power brightens the blue sky as much as the planet, meaning that it is no easier to hold the image with a sextant than to view Venus with a naked eye, hence making the observation impractical. Trevor Kenchington -- Trevor J. Kenchington PhD Gadus@iStar.ca Gadus Associates, Office(902) 889-9250 R.R.#1, Musquodoboit Harbour, Fax (902) 889-9251 Nova Scotia B0J 2L0, CANADA Home (902) 889-3555 Science Serving the Fisheries http://home.istar.ca/~gadus