You can pinpoint any place on Earth using a single set of coordinates: latitude and longitude. These coordinates look like a string of numbers. Once you have those numbers, you'll be able to plug them into a web map, GPS, or other mapping device and find what you're looking for in an instant -- no matter where on the planet it is.
Using latitude and longitude information makes it easy to find your ancestors' homestead, your own house, the county courthouse in a distant city, or any other location of genealogical interest.
The coordinates are similar to the Xs and Ys you used to plot in algebra class. Imagine if the surface of the Earth could be stretched flat. Then suppose you place a grid on top of the flattened world. You could pinpoint any location by finding the spot where the horizontal and vertical grid lines intersect. The horizontal x-axis is the equator, while the vertical y-axis is the Prime Meridian, which runs through the Greenwich Observatory in England.
Geographic coordinates can be expressed in three different formats:
* DMS Degrees: Minutes:Seconds (49°30'00"N, 123°30'00"W)
* DM Degrees:Decimal Minutes (49°30.0', -123°30.0'), (49d30.0m,-123d30.0')
* DD Decimal Degrees: (49.5000°,-123.5000°), generally with 4-6 decimal numbers.
Older maps typically use the DMS Degrees, expressed in degrees, minutes, and seconds. Computers like to work with decimals, however, and the majority of computer applications seem to use DD Decimal Degrees.
The letter "N" or "S" at the end of a latitude indicates that the location is north or south of the equator. In a similar manner, the letter "E" or "W" at the end of a longitude indicates that the location is east or west of the Greenwich Observatory in England. In the DD Decimal Degrees method, a minus sign on the latitude indicates south of the equator while a minus sign on a longitude indicates a location west of the Greenwich Observatory. Plus signs are assumed and therefore usually are omitted on latitudes north of the equator or longitudes east of the Greenwich Observatory.
There are many websites that will take an address and convert it to a point. Google Maps, for example, has to do this whenever you type a location into its search box. However, Google Maps does not make it easy to get the latitude and longitude of the resulting location.
A site that is easier to use is found at www.GetLatLon.com, a simple site made for this explicit purpose. The website asks for a "place name," such as a city, but you can type in many things. You can use a postal code, an airport code, or a full address. When you click the "Zoom to place" button, the map below will update to show the location.
I experimented with www.GetLatLon.com and entered my own home address. I quickly found the exact latitude and longitude of the house. I was amazed to see that the map drawn on the screen even included the property lines of each house lot. I am not sure if that is available for all locations, but it certainly works well in my neighborhood.
I found the Family History Library in Salt Lake City is at: Latitude, Longitude: 40.77040386721811, -111.89426600933075
The www.GetLatLon.com web site also works in the opposite direction: enter a latitude and longitude, and the web site will draw a map on the screen with that exact location in the center of the map. In my experiments, I entered "40.77040386721811, -111.89426600933075" and then clicked on Zoom to place. The www.GetLatLon.com site then displayed a map showing the Family History Library's exact location.
You might want to experiment at http://www.GetLatLon.com.