What do we need in order to locate places accurately on the surface of the Earth
Answers
Answer:
Explanation:
This lesson will explain how we can describe the location of points on the Earth's surface using latitude and longitude. We will also look at some applications of finding the shortest distance between two points on the Earth's surface.
Points on the Earth's Surface
Did you know that where you're sitting right now has an exact location, or point, on the Earth's surface? Furthermore, did you know that we have a system set up so that we can locate points on the Earth's surface? It's really quite fascinating. You see, the Earth is put on a grid of sorts that allows us to locate points on its surface.
Of course, the Earth is round, so its grid differs from a normal xy-coordinate system, but the concept is the same. We are able to locate points on the Earth's surface using the latitude and longitude of the point, and these are determined by the grid. Let's discuss these two concepts so this can all become more familiar.
Latitude and Longitude
Latitude is a point's angular distance from the Equator, where the Equator is an imaginary line that is exactly halfway between the North Pole and the South Pole and runs around the circumference of the Earth. Latitudinal lines are the horizontal lines of the Earth's grid that are parallel to the equator. They are measured in degrees from 0 to 90 degrees north or south of the equator. Points that lie above the Equator are given in degrees north, and points that lie below the Equator are given in degrees south.
Longitude is the angular distance of a point from the Prime Meridian, where the Prime Meridian is an imaginary line that runs perpendicular to the Equator from the North Pole to the South Pole and passes through Greenwich England. Longitudinal lines, also called meridians, differ from latitudinal lines in that they do not run parallel to the Prime Meridian. Rather, they are half circles with a radius equal to the Earth's radius (approximately 3960 miles), running from the North Pole to the South Pole. They are measured in degrees from 0 to 180 degrees east or west of the Prime Meridian. Points to the east of the Prime Meridian are given in degrees east, and points to the west of the Prime Meridian are given in degrees west.
Using latitude and longitude, we can locate points on the Earth's surface using the following format:
Latitude Degrees N or S, Longitude Degrees E or W
For example, in decimal degrees, the location of Grand Rapids, MI on the Earth's surface is 42.963 N, 85.668 W. This tells us that Grand Rapids, MI lies 42.963 degrees north of the Equator and 85.668 degrees west of the Prime Meridian.