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    Re: Daylight Venus and Daylight Saving
    From: David C
    Date: 2022 Mar 12, 20:54 -0800

    At 1022 NZDST today (0908 local mean time) the sky was cloudy. An hour later it had cleared so I began the search for venus using 7 x 5 binoculars.  To the north there  is a ridge line with  distinctive shapes and trees. I know where north is and suddenly realised that I could  identify venus' hour angle marker using my sextant to measure a horizontal angle  from north. It seemed to work because I locked onto venus with the binoculars. However when I looked away I could not find it. Twice I saw glimpses of venus but coud not lock on again. My problem is estimating the high altitude even though I use the nearby sun as a reference. I tried lying on the grass so I was looking approximately at the zenith and then moving my eyes down. It did not work. My aging eyes may be a problem. Something visible at 7x mgnification may not be visible at 1x.

    I use these venus challenges to practice the basics of CN namely time:

    For my location

    NZDST = UT + 13

    longitude   175°  05.2106'

    delta long (from date line )   4° 54'  47" = 4.91317°

    delta long in time 4.91317  / 360 * 24 = 0.3275 hours      = 19.65 minutes

    local mean time  - NZDST -  delta long

    Want to use am/pm notation so throwaway 12 hours

    0908  - NZDST +1  - 19.65

    From which NZDST = 1008 + 20

    and  NZDST =   1028 when local mean time is 9 08 am.

    The dec of venus is 16°S. I am at lat 41°S so same names.  I decided to be clever and  use Burdwood to confirm that the azimuth of venus is 0° at 9 08am local time. The method did not work because Burdwood gives the sun's azimith!!!!! It had me confused and puzzled for a while................

       
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