Forum: Questions And Answers About Geocaching
Topic: Digital Compass
started by: MOCache
Posted by MOCache on Dec. 20 2003,9:11 amOK, I'll bite.. can anyone tell me briefly how you can use a compass to find latitude and longitude?
Posted by welch on Dec. 20 2003,12:39 pm
hmm... wouldn't you need a map of the area and something to measure distance? (trianglulate from known landmarks???)
Posted by PC Medic on Dec. 20 2003,1:45 pmNow it has been quite some time since my military days and compass training, but I do not believe it would be possible with just a compass. As Welch said you would need a map at least (and one marked with a grid) and then presuming you new the lat/lon for your starting point you should be able to move about from there with the compass and get at least a real close idea as to your current position.
To check accuracy, just call for some mortar fire
Posted by DustyJacket on Dec. 20 2003,5:00 pmYou sell the compass to someone who will give you the Lat/Long in return. Or buy a map and lat/long scale with the proceeds.
Posted by Volvo Man on Dec. 22 2003,12:35 amI guess, if you travelled east-west only, you could work out the rate of deflection of north vs distance travelled, that would give you your latitude, although not which side of the equator you are on. then, if you stand very still, and it's a clear day, you could plot the time of the sunset and the bearing of the setting sun, which, coupled with the date would give you the ability to work out both your longitude and which side of the equator you are on.
you wouldn't even need to know the date if you could stay in the same spot long enough, you could make solar observations and derive the date from that. you still need an accurate watch though, which may as well have the date on it.
Sounds simple doesn't it? it all relies on some pretty extreme trig calculations which are best left to scientific calculators, but you could feasibly do them on paper if your name's albert einstein.
remember, nothing's impossible, just highly improbable.