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Re: Sextant accuracy (was : Plumb-line horizon vs. geocentric horizon)
From: Alexandre Eremenko
Date: 2005 Feb 13, 22:04 -0500
From: Alexandre Eremenko
Date: 2005 Feb 13, 22:04 -0500
Actually I thought first that the black dots on the Sun disc are specs on my lenses:-) Only later I recalled from optics that specs on the lenses (or on the mirrors) will not be visible through a telescope, and that these black dots occur in the same places every day... So I repeated Galileo's discovery:-) Alex. On Sun, 13 Feb 2005, Frank Reed wrote: > Alex: > "Another similar exercise (and simpler one!) would be > to draw a map of sun spots as seen through your sextant. > I actually have never seen sun spots "alive" before I bought a > sextant:-)" > > Fun, isn't it? That's a good idea, too. It would be a good resolution > experiment since you could compare with near real-time sun images online (or haul > out a bigger telescope). > > -FER > 42.0N 87.7W, or 41.4N 72.1W. > www.HistoricalAtlas.com/lunars >
