ABSOTE LOCATION

• Where on Earth are you? Navigators use lines of latitude, which run east and west (sideways, or horizontally) around Earth, and lines of longitude, which run north and south (up and down, or vertically) around Earth. These lines create kind of an imaginary graph paper on the Earth that makes it possible to find an absolute (exact) location on Earth. They even allow us to give an absolute location to a place out in the middle of the ocean.
• Lines of latitude tell us how far north or south of the equator we are. Sailors have used primitive navigation tools, like astrolabes, to help them approximate their distance from the equator since the 1400’s. Although their instruments may not have been very state of the art, they were incredibly accurate for their time.
• Lines of longitude tell us how far east or west of the prime meridian we are. Although sailors were constantly looking for new ways to increase their knowledge of navigation, it was another 300 years before they were able to accurately measure degrees of longitude. They would have been very envious of the technology available to us today.
• When we use lines of latitude and longitude together, we can get a very precise location. The lines of latitude and longitude that cross each other nearest the point we wish to identify give us the coordinates for that place’s absolute location. Many maps today include a grid that allows you to see degrees of latitude and longitude on top of the continents of the world.
• Another tool that helped us develop our knowledge about navigation is the magnetic compass. The magnetic compass was developed in China. Sailors brought it from China to Europe in the 1400’s during their regular trade expeditions to Asia. Technology like the compass and the astrolabe, a tool that let sailors use the sun and stars to find their approximate location, made worldwide travel easier, and encouraged more exploration.

 Name:__________________________________

Answer the following questions based on the reading passage. Don’t forget to go back to the passage whenever necessary to find or confirm your  answers.

1)   What is the function of lines of latitude and longitude?

2)   Do you think that America would have developed as a colony if the magnetic compass had not been developed? Why or why not?

3)      Explain what is meant by an absolute location.

   4)   In your opinion, which invention was more important, the astrolabe, or the magnetic compass? Why?

   5)   What could you invent that would make it even easier to locate places on Earth today?