Subject:What is the difference between latitude and longitude?
Ref: http://loki.ur.utk.edu/ut2kids/maps/lat&long.html
Think of the world as an orange. If you insert a needle through the center of the orange, the top of the needle would be the North Pole and the bottom of the needle would be the South Pole.
Longitude lines (meridians) are north (up) to south (down) or vertical lines on a globe or map. If you cut the orange in equal halves from the North Pole to the South Pole you make lines of longitude.
Longitude lines (Meridians)
The most famous line of longitude is the prime meridian which passes through Greenwich, England. The prime meridian is at 0 degrees longitude. There are 180 degrees of longitude to the east (right) and 180 degrees of longitude to the west (left) of the prime meridian. Knoxville, Tennessee is near the 84 degree west longitude meridian.
Latitude lines (parallels) run west to east (side-to-side or horizontal).
Only one line, called the equator, will divide the earth into two equal parts (the Northern and Southern Hemispheres). The equator is at 0 degrees latitude. There are 90 degrees of latitude to the north (above) and 90 degrees of latitude to the south (below) the equator. Some famous lines of latitude south of the equator are the Tropic of Capricorn (23.5 degrees south) and The Antarctic Circle (66.5 degrees south). North of the equator are the Tropic of Cancer (23.5 degrees north) and the Arctic Circle (66.5 degrees north). Knoxville, Tennessee is near the 36 degree north latitude parallel.
How do you find the latitude and longitude of your house?
The easiest way is to look at an atlas. Find where you live. Then look for the nearest north and south (up and down) line to get longitude and the nearest east to west (side-to-side) line to get latitude. Although you may not live right on a line, you can estimate your latitude and longitude. For example:
If you look on a world atlas you will see that Knoxville, Tennessee is near the 36 degree north latitude parallel and the 84 degree west longitude meridian.
How does a scientist in the middle of the ocean or desert find his/her latitude and longitude?
Scientists, like those on the Polar Duke in Search for Antarctic Spring, use a Global Positioning System (GPS). To use the GPS you need a piece of equipment, called a receiver, that is capable of sending a signal to satellites orbiting above the earth. The receiver then finds out how long it takes for a signal it sends to be received by the satellite. Using the length of time for the signal to get to the satellite and the satellite's position in orbit, the receiver can compute its exact latitude and longitude.