NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Position from a Clock with Photo Diode
From: Frank Reed CT
Date: 2005 Jun 6, 23:00 EDT
From: Frank Reed CT
Date: 2005 Jun 6, 23:00 EDT
Brooke C you wrote: "Suppose that a clock that keeps UTC time to within 1 second has a photo sensor with an analog output to a computer. The clock is indoors but the room has a window to the outside so although the clock is in the shadow of the Sun it does see a daily brightness curve. How accurately can the clock determine where it is in the world?" This exists. In fish tags!! I've posted on this before. Here's something I wrote previously: >>This technique of navigation is actively employed on a small device that operates in an area inaccessible to GPS signals --underwater. Do you have $4200 to spare? Then you, too, can be the proud honor of a celestial navigating fish tag. I brought this up briefly on the list over a year ago. Here's a link to their web site and a description of the device: http://microwavetelemetry.com/Fish_PTTs/archival.php They get one-degree-ish estimated accuracy in latitude and longitude by timing sunrise and sunset (based on light levels corrected for depth, which is measured by pressure). << -FER 42.0N 87.7W, or 41.4N 72.1W. www.HistoricalAtlas.com/lunars
