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    Re: Venus transit June 8 and sextants
    From: Robert Eno
    Date: 2004 May 11, 19:56 -0400

    Frank Reed wrote:
    When I want to look at the Sun through a sextant --maybe to see sunspots,
    for example-- I usually set the arm to the Sun's approximate altitude and
    then hold the instrument in the usual orientation for altitude sights. This
    is convenient ergonomically (no neck strain) and it also means that you're
    not looking towards the Sun so there's less glare. But there's nothing more
    dangerous here than the limb-to-limb procedure for measuring index error, so
    if you want to set the instrument to zero, swing in the horizon shades, and
    aim it up into the sky, there's no particular problem. We know sextant
    shades are safe for that purpose. The transit's in progress for eastern
    Canada, so there's probably little practical difference for you.
    Robert asks?
    Why is this dangerous?  Is it because there is a possibility of the shades
    slipping out of position?

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