Navigation, in its simplest form, means to find your way to a point and back again. For sailors, navigation means guiding a ship through water without the help of road signs. Early sailors navigated in inland rivers and waterways which was simple. When sailors ventured out into the sea, they remained close to the coastline, using towns and the shoreline to mark their journey. A sailor's feel for the sea, the directional guidance of the sun, landmarks, and oral directions framed the earliest navigational aids.
Later, sailors looked to the heavens for a more reliable means of navigation. The development of the compass and the quadrant allowed sailors to move with some certainty on the sea. Using the North Star as a landmark, sailors sighted the star with a quadrant, measured the angle from the horizon and identified the latitude. Once the ship reached the correct latitude, it sailed east or west to reach its destination. Sailors could tell how far they were going in either direction by locating the lines of longitude. Nautical direction was determined by the magnetic needle of a compass. In the days of sail, courses and bearings were given in points around a compass.
Soon, sailors began to draw charts and record their paths and directions. In 1842 Matthew Fontaine Maury, a United States Naval officer, instituted a series of Wind and Current Charts and Sailing Directs. These charts and publications established ship lanes and revolutionized navigation on the seas. In the 20th century navigation became more reliable and sophisticated. During World War II, sailors used different types of radio wave navigation to help planes and ships find their locations, as well as find enemy ships. Today, sailors on most large ships use satellite and computer technology, such as GPS (Global Positioning Satellietes), to guide them on the seas.
Questions and Activities
The following activities may be completed individually or as a group.
1. Imagine that you need to give directions to someone from your school to your home. You may write the directions any way you would like, for example, using landmarks, directional terms, or distance. Remember that this person has never been to your home before, so your directions must be detailed and precise. What tools or clues do you think are most effective when giving someone directions?
2. Using a local road atlas or map of your community, find the precise latitude and longitude of your local hospital, school, and public library. Using the same map or atlas describe how you would get to each location from your home. What is the distance to each location from your home? Use the distance chart at the bottom of the map.
For questions 1 & 2 be sure that you bring in a copy of the map or atlas pages that you used so your teacher can better understand your directions.
3. Do you think it is easier to map a course on land or on the ocean? Why?
4. Imagine you are on a ship trying to get from your classroom to another class, gym, or playground at your school. Working in a team or on your own, create a map. Provide directions (left and right) and approximate distances (4 steps, 30 seconds). When maps are complete exchange them with your classmates and see if you can follow their maps.
5. Using a globe or map find lines of longitude and latitude. Can you find the approximate location of Washington, DC? Try to find the following locations and list their latitude and longitude:
Los Angeles, CA
Mexico City, Mexico
There may be more then one degree of latitude and longitude for these areas of the world. That's okay! You only need to pick one.
6. Using a globe, find these coordinates. Write down their location.
90°N 26° W