Last night I had an attack of randomitisness. This happens to me periodically as I have complete random thoughts and then have to investigate them. I don't know if others suffer from this scourge, but it is something that I must deal with on a random and continual basis.
Last night's influx dealt with the issue of the distance of an arc-second. I know that particular word will likely keep North of 50 from reading any further as his long-ago post "What I Learned in Algebra and Geometry" shall attest. Though his knowledge of subjects is wide and varied, he's a little lax on the sciences.
Several years ago before the popular advent of GPS devices I decided to find the map co-ordinances of my home. It took some doing but I was at last able to decipher them. I used the internet to track the latitude and longitude but had to convert them to the degree, minute and second designations. Still with me North? I also sent him the location of his home which is not far from mine.
Last night, I wondered what the length of an arc-second was. For the uninitiated, if you divide the earth's circle into 360 segments, each one is a degree, hence that is what is taught in geometry. Degrees are then sub-divided into 60 parts (minutes) and those minutes to another 60 (seconds). North, wake up! The problem you run into is in dealing with longitude. As you move north or south on the globe, the distance of an arc-second decreases. (OK, I'm sure North is completely gone by now). That being said, most use the distance on the equator as the standard. To that end, the distance of an arc-second at the equator is approximately 101 feet, just in case anyone wanted to know.
N39* 55' 1"
W-82* 45' 29"