It has horizontal lines and vertical lines that intersect. A location can be mapped or found on a grid system simply by giving two numbers which are the location's horizontal and vertical coordinates; or, to say it another way, the "intersection" where the place is located.
Latitude Horizontal mapping lines on Earth are lines of latitude. They are known as "parallels" of latitude, because they run parallel to the equator. One simple way to visualize this might be to think about having imaginary horizontal "hula hoops" around the earth, with the biggest hoop around the equator, and then progressively smaller ones stacked above and below it to reach the North and South Poles.
Can you think of other ways to visualize the parallels of Latitude? Think about having imaginary horizontal "hula hoops" around the earth, with the biggest hoop around the equator, and then progressively smaller ones stacked above and below it to reach the North and South Poles. Latitude lines are a numerical way to measure how far north or south of the equator a place is located.
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All content. Make a quadrant similar to the one shown here. The aiming beam needs to be pivoted about its central point so that it can swing up and down. The protractor should be centred on the pivot, from which the plumb line should be suspended.
A quadrant for measuring latitude Measuring latitude using the sun can only be done at noon, when the sun is at its highest point in the sky.
To determine when it's noon without a watch or radio place a stick at the southernmost end of your north-south line. Use a plumb line to make sure that the stick is vertical. When the shadow cast by the stick crosses the north-south line, it's noon. As soon as it's noon, align the sighting nails on the quadrant's aiming beam with the sun. Two shadows on the groud - beam aimed incorrectly When the shadows coincide, the beam is aimed exactly at the sun.
One shadow - beam aimed correctly If the sun is directly over the Equator, this is your latitude reading. Unfortunately, this reading is only correct on 21 March and 21 September the spring and autumn equinoxes. At midwinter 21 December you should deduct This is because of the way in which the 'tilted' Earth orbits the sun. Using the North Star to measure latitude Once you've found the North Star it's simple to determine your latitude.
Look along the back of the 'Plough blade'. About four blade-lengths along is the North Star. The constellation Cassiopeia is about the same distance from the North Star, but on the opposite side of it from the Plough. As the North Star is roughly in line with the Earth's axis of rotation, it never changes position, and measurements can be taken with the quadrant at any time of the night, whatever the season.
Construct a device to work out local noon, like a north—south line. No problem! Further reading. Cox J. Read a related article Copyright: The Open University. Latitude and Longitude When people began to travel long distances over deserts or seas, they needed a way to fix their position. Read now Latitude and Longitude. Article Level: 1 Introductory. Article Level: 2 Intermediate. Study a free Geography course Used with permission. Used with permission. Become an OU student. Copyright information.
Publication details Originally published : Thursday, 31st August Last updated on : Friday, 1st March Leave a comment.
Sign in or create your OpenLearn account to join the discussion. Feeds If you enjoyed this, why not follow a feed to find out when we have new things like it? Related content tags. Figure 2. Meridians or "Lines of Longitude" and degree readings for longitudes in increments of 30 degrees. Parallels or "Lines of Latitude" and degree readings for latitudes in increments of 30 degrees.
Note that the lines are parallel when we look at the earth from the equator. If we look at them from the poles, they appear circular. The latitude is the angle formed by a line going from the center of the earth to the equator at the point on the equator that is closed to the point of interest and another line that goes from the center of the earth to the parallel that goes through the point of interest.
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