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    Re: Faint stars easier to find on the horizon first?
    From: Fred Hebard
    Date: 2004 May 28, 08:34 -0400

    I have seen suggestions to use Venus in the day in some texts.
    On May 28, 2004, at 4:55 AM, Trevor J. Kenchington wrote:
    > 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
    >                      http://home.istar.ca/~gadus

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