I've been having fun with a new "toy." A nice little handheld GPS (global positioning system) receiver bought at a bargain price at a local big box store. Following my progress on the scrolling map image during a morning commute made the trip a lot more fun.
Surprising to me was how quickly the GPS was able to update and display my travel speed as I drove. After all, the little palm-sized unit was receiving signals from several orbiting satellites a little more than 12,000 miles high, comparing their time signals, calculating my position in three dimensions and its rate of change, and displaying it on a little LCD screen, all with only a couple of seconds lag time! And, optimally, to within about 10 feet of my exact location. Following travel progress on the unit's built-in map was fun (for map geeks like me) but a little too distracting if you're driving. I'm looking forward to my next stint as a passenger!
Of course there are many practical uses that spring out of such accuracy and built-in features. Use a GPS to help you find your way to a place or back from it. Mark a place in the GPS memory discovered by happy accident and easily find your way back to it. Using a computer with electronic maps, chart your cross-country hike or bike ride. Walkers can use a little GPS in place of a pedometer and get more than simple mileage information in the bargain. (My walk from the parking lot to the door of the building was at 3.2 MPH, says the GPS.) Modern amateur astronomers can key GPS coordinates into their computerized telescopes to help refine their pointing accuracy.
The availability of inexpensive handheld GPSes has even spawned the rise of a fun new activity: geocaching. It's much like traditional orienteering but uses satellite navigation in place of magnetic compass headings. We've seen geocachers roaming Westlake, including the library's lot on occasion.
So a system that was created to make extremely accurate the movement of troops and delivery of weapons is now also used by others: civilian boaters, hikers, bikers, and drivers headed to grandma's house. And by stargazers on their way to their day jobs just for the fun of it. Interesting the way things develop.
Here's a good Wikipedia article on GPS: what it is, how it works, and what we can do with it.
In case you're navigating your way to the library, the coordinates for our front door are: 41° 26.856N by 81° 55.441W.