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THE ONLY WAY IS UP!
Latitude & Longitude
Mayday, Mayday, Mayday - 40O N 20OW. This was the message that came over the radio receiver. It meant that a ship was in distress sinking somewhere in one of the world's oceans. 'Mayday ' sounds like 'm'aider ' which means 'help me in French - but where is 40O N 20OW? The message is a short way of saying: 40 degrees north of latitude 0; and 20 degrees west of longitude 0. To help pinpoint ships and aeroplanes, lines of latitude and longitude are drawn on the world map until it looks like a grid. Latitude 0O is a line which goes round the middle of the earth and is called the Equator. Longitude 0O goes from top to bottom on the earth and goes through Greenwich. Other lines of latitude and longitude are drawn on parallel to these two. By finding where latitude line 40ON meets longitude 20OW, the ship's position can be found. Now at least other ships will know where to start looking for survivors.
Latitude is the angular distance of any object from the equator measured in degrees. The angular distance from the equator to itself is 0, thus the latitude at the equator is 0 °. They always go from North to South!
Just remember: LATTIES ARE FATTIES AND FATTIES GO FIRST!
As we have already read, the lines extending around the Earth horizontally are called lines of latitude. They measure how far north or south an object is on the Earth. The lines running vertically around the Earth are called longitude. These lines are called meridians, and measure how far east or west an object is. These always go from East to West!!!
Greenwich Mean Time (GMT) is the mean solar time at the Royal Greenwich Observatory in Grennwich near London, England, which by convention is at 0 degrees geographic longitude. Theoretically, noon Greenwich Mean Time is the moment when the Sun crosses the Greenwich meridian (and reaches its highest point in the sky in Greenwich).
So where exactly is the North Pole? Well, the Earth rotates or spins around an axis. If you were to draw a line at the axis through the center of the Earth, that line would exit the Earth in two places. At the bottom of the Earth, it would exit at the South Pole and at the top would be the North Pole. The North Pole is the northernmost place on Earth.
The Tropic of Cancer is one of the five major circles of latitude that mark maps of the Earth. This is the parallel of latitude that runs 23.5°N of the Equator, and is the farthest northern latitude at which the sun can appear directly overhead. North of this line is the Northern Temperate Zone. South of this line are the Tropics. This line is called the Tropic of Cancer because, when the sun appears directly overhead, at this latitude, during thesummer solstice, it is entering the zodiac sign of Cancer.
The South Pole is the southernmost point on the Earth. It is the precise point of the southern intersection of the Earth'saxis and the Earth's surface. From the South Pole, all directions are north. Its latitude is 90 degrees south, and all lines of longitude meet there (as well as at the North Pole, on the opposite end of the Earth).
The prime meridian is the imaginary line that divides Earth into two equal parts: the Eastern Hemisphere and the Western Hemisphere. The prime meridian is also used as the basis for the world's time zones.
The Tropic of Capricorn is the parallel of latitude that runs approximately 23.5 5°S of the Equator, and is the farthest southern latitude at which the sun can appear directly overhead. This line is called the Tropic of Capricorn because about 2000 years ago, when it was named, the sun appeared directly overhead, at this latitude, during the winter solstice, it was entering the zodiac sign of Capricorn. Now, the sun appears in the constellation sagittarius at its southern most point. The change is due to precession.
The Equator is an imaginary circle around Earth. It divides Earth into two equal parts: the Northern Hemisphere and the Southern Hemisphere.
It runs east and west halfway between the North and South poles. The distance around the Equator is about 24,900 miles (40,000 kilometres).
The International Date Line is an imaginary line on the surface of the Earth that sits mostly on the 180º line of longitude in the middle of the Pacific Ocean. The International Date Line lies on the opposite side of the world to the Prime Meridian (The Prime Meridian passes through Greenwich in London. It separates the Eastern and Western Hemispheres). The International Date Line separates two consecutive calendar days.Immediately to the left of the International Date Line (the date) is always one day ahead of the date (or day) immediately to the rightof the International Date Line in the Western Hemisphere. People crossing the line from East to the West skip forward a day. Those crossing from the West to the East repeat the day.
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