How to Determine Latitude

When you want to point your satellite dish or map an orienteering trip in the woods, knowing your latitude can be very handy. Handheld GPS devices make finding your latitude and longitude easy, but there are other methods that work as well.

Instructions

1. Use a hand-held GPS unit. Turn the unit on and make sure that it is picking up its satellite connections properly. The first set of numbers on the GPS will be your latitude. The second set of numbers is your longitude.

2. Look up the latitude of your town or city up on the Internet or on a map. This works as long as you don't need an exact number. Many websites list the coordinates of major world cities and this gives you your position to the nearest minute or so.

3. Measure the altitude of the sun above the horizon with a sextant when it reaches its highest point in the sky around noon. You need a watch and an almanac that gives the declination of the sun and the time of its highest altitude for the current day. The difference between the sun's highest altitude and its declination gives you your latitude.

4. Guess based on the height of the North Star at night. Ninety minus the number of degrees between the horizon and the North Star gives you your latitude. This only works if you live in the Northern Hemisphere.

Resources

• List of Latitudes for U.S. Cities
• List of Latitudes for Canadian Cities