{"id":1279,"date":"2008-10-14T06:42:20","date_gmt":"2008-10-14T10:42:20","guid":{"rendered":"http:\/\/johnesimpson.com\/blog\/?p=1279"},"modified":"2008-10-15T16:22:41","modified_gmt":"2008-10-15T20:22:41","slug":"the-travels-of-mickey-tom-1","status":"publish","type":"post","link":"https:\/\/johnesimpson.com\/blog\/2008\/10\/the-travels-of-mickey-tom-1\/","title":{"rendered":"The Travels of Mickey Tom (1)"},"content":{"rendered":"

\"\"In the second part of this two-part series, I’ll introduce you to a handsome fellow named Mickey Tom. I’ll tell you where he started out, where he is now, how he got<\/em> to where he is now, and where he’s headed.<\/p>\n

But before I can do any of that, I need to provide some background for readers who might not be familiar with a particular, some would say peculiar<\/em>… hmm… pastime? hobby? obsession? adventuring nerd’s side quest?<\/p>\n

Any of those terms might suffice as a descriptor for the mysterious word geocaching<\/em>.<\/p>\n

If you’ve paid attention to car commercials in the last couple of years, you probably already know the phrase “GPS unit.” This is a small boxy electronic gizmo, typically mounted on the dashboard, which displays a real-time map of the route you’re currently driving. Sophisticated GPS units allow you to specify a destination, for which the machine will select an optimal route to follow; some of them even “talk,” instructing you audibly to (for instance) “Turn left here.”<\/p>\n

The main technology which allows car GPS units to work is a network of satellites, collectively called the Global Positioning System. The idea is fairly simple; at root, it’s just geometry: If you know the positions of at least three objects, and can determine your distance from each of them, then you can determine your own<\/em> position. As the GPS satellites circle the globe, they beam down to earth a signal reporting their current positions. Any device which can receive those transmissions thus can figure out — to a more or less accurate degree — the device’s own latitude and longitude.<\/p>\n

That’s all you need to understand in order to “understand” how geocaching works. But that still doesn’t say much about geocaching itself, does it?<\/p>\n

Read on.<\/p>\n

<\/p>\n

That these GPS satellites’ signals were actually made public rather than being held secret by the military is one of the great unremarked public-policy marvels of the last ten years or so. But public they are — which is why the dashboard units work at all.<\/p>\n

And in fact, the popular dashboard units were preceded by smaller, handheld GPS devices. (That’s the main screen of one such device above — not far from actual size.) As with the ones made for cars, a handheld GPS unit enables you to pinpoint where you are relative to the satellites — but also relative to other known fixed points on the Earth’s surface, like monuments, libraries, and other buildings, interstate highways and county roads, parks, cellular antennas…<\/p>\n

Unlike the units made for cars, though, handheld GPS units don’t tie you to roads. If you can get somewhere on foot — and with some other minor restrictions — your handheld device can tell you where on earth you are, within a few feet one way or another.<\/p>\n

And that’s what some genius took advantage of when s\/he came up with the idea of geocaching.<\/p>\n

In its general form, geocaching resembles participating in a scavenger hunt. The difference is, you know (more or less accurately) exactly where<\/em> to find a “treasure”; you just don’t know what<\/em> you might find when you get there.<\/p>\n

This is the moment, probably, to introduce you to the Grand Central Station of geocachers, the site known (duh) as geocaching.com<\/a>. From that home page:<\/p>\n

Geocaching is a high-tech treasure hunting game played throughout the world by adventure seekers equipped with GPS devices. The basic idea is to locate hidden containers, called geocaches, outdoors and then share your experiences online. Geocaching is enjoyed by people from all age groups, with a strong sense of community and support for the environment.<\/p><\/blockquote>\n

Got that? Not only does a geocacher operate outdoors; s\/he also contributes online<\/em>. (At geocaching.com, obviously.)<\/p>\n

How many geocaches — hidden treasure troves — are there? As the home page says, they currently number almost 700,000, spread all around the world. You can key in your postal code or address, and find out just how many are within a few miles. For instance:<\/p>\n