NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2012 Jan 25, 06:59 -0800
Geoffrey,
I have been able to observe daytime Sirius using a 4 power sextant scope. Since Sirius is 23 times as bright as Polaris then a 92 power scope should do the trick.
Greg Rudzinski
[NavList] Polaris in daytime
From: Geoffrey Kolbe
Date: 25 Jan 2012 14:31
Surveyors often need to find true North to lay out the initial
reference line off which a building is measured. These days, with GPS
gizmos, there is no difficulty in this. But pre-GPS, true North was
found by taking a timed azimuth measurement of the sun, or of Polaris
which, the text books say, is visible during the day using the
average theodolite 30x scope.
When I was in Egypt a few years ago doing an experiment on pyramid
alignment, I tried to find Polaris using my theodolite. I had taken
azimuth measurements off the sun, so I knew where to look, but I
never saw nothing. Polaris is too high in these latitudes (Scotland)
to see with a theodolite, so I am not able to try here.
Has anyone in lower latitudes managed to see Polaris in the daytime
through their sextant telescope, or through any other telescope? I
was wondering how big a telescope you need to see Polaris in the daytime.
Thanks
Geoffrey Kolbe
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