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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Venus transit June 8 and sextants
From: Robert Eno
Date: 2004 May 11, 19:56 -0400
From: Robert Eno
Date: 2004 May 11, 19:56 -0400
Frank Reed wrote: Ouch! 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?
