NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: sextant index error measurement
From: Bill B
Date: 2006 Nov 09, 02:56 -0500
From: Bill B
Date: 2006 Nov 09, 02:56 -0500
Frank wrote: > Just for fun, let's imagine an extreme exception... Take your sextant out to a > parking lot with nice black asphalt surfacing on a calm summer day just after > sunrise. Set it up vertically just above the surface and wait. As the Sun > heats the surface a layer of hot air will form over the parking lot. Without > wind, the hot layer will not immediately mix fully with the cooler air above > it. The density gradient will be substantial, and the refraction will be > measurably different. As the doctor says in the old joke, "Vell, don't do > that!". > Hence my caveat of a light breeze for the K-Mart parking-lot site. But you do lend support to my after-market product. It is either a fan or compressed-air device that can be mounted on the sextant to mix the air in front of the sextant.Bill --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---