GPS - Global Positioning System
The Global Positioning System has at its heart a network of satellites (24) in orbit. These satellites send out radio frequencies that can be detected by each other and by a variety of earth-bound objects with the right software and hardware. A GPS device needs only to be able to pick ip signals from four of the satellites to be able to figure out where it is, to an incredibly accurate degree - about 10 metres on the surface, or 100 metres of altitude.
Originally used by the military, GPS devices have been adopted by many regular people for a wide variety of uses. There are groups dedicated to sharing information using the coordinates or "waypoints" (latitude and longitude), such as where to find the best fish, or where to take some great pictures. There is even a great game that is a modern version of treasure hunting called "Geocaching" (see inset).
You don't necessarily have to invest in a GPS device, as other handheld devices (like your Palm Pilot or GameBoy Advanced) can be converted into GPS devices, with the addition of the right software application. Of course, there are also some cool additional functions available when you look for the right GPS device that you may not get by simply converting another tool to this purpose.
Geocaching
From Wikipedia, the free encyclopedia. (http://en.wikipedia.org/wiki/Geocaching)
Geocaching is an outdoor sport that involves the use of a Global Positioning System ("GPS") receiver to find a "geocache" (or "cache") placed anywhere in the world. A typical cache is a small, waterproof container containing a logbook and "treasure". Geocaching is a unique take on an earlier game called Letterboxing in that it uses two recent technologies, the GPS and the Internet. Participants are called geocachers.
The sport of geocaching was made possible by the "turning off" of the Selective Availability of the Global Positioning System on May 1, 2000. The first documented placement of a cache with GPS assistance took place on May 3, 2000 by Dave Ulmer. The location was posted on the Usenet newsgroup sci.geo.satellite-nav. By May 6, 2000 it had been found twice and logged once.
Geocaching is growing rapidly in popularity all over the world. As of June 2, 2005 there were 171,116 active caches in 215 countries posted on geocaching.com (http://www.geocaching.com).
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Satefy tips:
- Watch the weather. A storm can seem to appear suddenly if you are not watching the sky as well as the scenery.
- Let someone know where you are going. Let them know the route you will be taking as well as your destination.
- Know and respect your limitations. That goes for everyone in the group. Don't put people in danger of heart attacks, asthma attacks, heatstroke, fatigue, drowning, etc. If you are in a remote area, it will take a long time for help to arrive.
More detailed safety information is available here.
Some cool GPS-based tools:
Links:
Be safe and have fun!
