Which parallels are great circles

A great circle has the same circumference , or outer boundary, and the same center point as its sphere. The geometry of spheres is useful for mapping the Earth and other planets. The Earth is not a perfect sphere, but it maintains the general shape. All the meridian s on Earth are great circles. Meridians, including the prime meridian , are the north-south lines we use to help describe exactly where we are on the Earth.

All these lines of longitude meet at the pole s, cutting the Earth neatly in half. The Equator is another of the Earth's great circles. If you were to cut into the Earth right on its Equator, you'd have two equal halves: the Northern and Southern Hemisphere s. The Equator is the only east-west line that is a great circle. All other parallels lines of latitude get smaller as you get near the poles. Great circles can be found on spheres as big as planets and as small as oranges.

If you cut an orange exactly in half, the line you cut is the orange's great circle. And until you eat one or both halves, you have two equal hemisphere s of the same orange.

Great circles are also useful in planning route s. The shortest path between two points on the surface of a sphere is always a segment of a great circle. Plotting great circles comes in very handy for airplane pilots trying to fly the shortest distance between two points. For example, if you flew from Atlanta, Georgia, to Athens, Greece, you could fly roughly along the path of one of Earth's great circles, which would be the shortest distance between those two points.

When planning routes, however, pilots have to take other factors into account, such as air current s and weather. Great circles are just general paths to follow. Equatorial Bulge Great circles on Earth are roughly 40, kilometers 24, miles all the way around. Each meridian is half of a great circle.

They run in a true north-south direction from. They are spaced farthest apart at the equator but. Meridians help us to determine standard time. Latitudes are also called Parallels. Longitudes and Latitudes are expressed in degrees, minutes and seconds. Some Important Latitudes:. Equator Latitude 0 o. Tropic of Cancer Latitude Tropic of Capricorn Latitude Arctic Circle Latitude Antarctic Circle Latitude Characteristics of Latitudes:. Aside the equator, all latitudes are small circles.

Always parallel to one another. True east-west lines. Important for the determination of the climatic. Geographic Grid is used to identify locations on the earth. A modern instrument for determining locations is termed Global Positioning System. A Great Circle is a plane that passes through the center of the earth. Equator and all Meridians. The shortest distance between any two points on the earth's surface is attained along the arc of a Great Circle.

Small Circles are lines that do not pass through the center of the earth. All Parallels other than the Equator are Small Circles. The earth undergoes one complete rotation along its axis in 24 hours. For a complete rotation on its axis, the earth passes through degrees. The earth rotates in an anti-clockwise direction From West towards East. The geometry of spheres is useful for mapping the Earth and other planets. The Earth is not a perfect sphere, but it maintains the general shape.

All the meridian s on Earth are great circles. Meridians, including the prime meridian , are the north-south lines we use to help describe exactly where we are on the Earth. All these lines of longitude meet at the pole s, cutting the Earth neatly in half. The Equator is another of the Earth's great circles. If you were to cut into the Earth right on its Equator, you'd have two equal halves: the Northern and Southern Hemisphere s.