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    Venus ex-meridian
    From: Federico Rossi
    Date: 2011 Jan 16, 21:59 +0100

    This morning, after weeks of cloudy weather, a beautiful sun was shining
    over Genoa, Italy so I took my 1940 Plath sextant, reached the shore (44
    25.5 N 8 48.8 E by GPS) which is only 5 minutes away by feet and took my
    first Venus sight in full daylight.
    I preset the sextant to the precomputed altitude and, after some tries,
    I finally spotted Venus with its phase clearly visible through my 3.5 x
    Here's what I got:
    08 50 31 UT      Hs 26 37,1    I.C. = 0     elevation 4 meters
    I worked out the sight using the haversine method and Norie's tables (as
    I usually like to do) and found an intercept of 0.8 miles towards (which
    I consider not too bad considering the task of collimating Venus with a
    bright horizon), azimuth being 189,5 by ABC tables.
    Since the hour angle was within ex-meridian limits (8 52.0 W), I decided
    to work the sight as an ex-meridian and found that the position line
    passes through 44 24,5 N 8 48,8 E (in good accordance with the "normal"
    position, but only 0.2 miles towards Venus). Anyway, this ex-meridian
    reduction took almost the same time as the haversine did.......

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