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    Re: Faint stars easier to find on the horizon first?
    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{at}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

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