Latitude
Latitude is used to express how far north or south you are, relative to the equator. If you are on the equator your latitude is zero. If you are near the north pole your latitude is nearly 90 degrees north. If you are near the south pole your latitude is almost 90 degrees south.
Conventionally latitude is expressed as degrees north or south. For inputting to the satellite dish pointing calculator, south latitude figures need to be input as negative numbers.
Note that from small regions around the north or south poles you cannot see geostationary satellites at all. The geostationary satellites are below the horizon and directly above the equator, in a circle all around.Longitude
Longitude shows your location in an east-west direction, relative to the Greenwich meridian. Places to the east of Greenwich (such as Middle East, India and Japan) have longitude angles up to 180 degrees east. Places to the west of Greenwich (such as the Atlantic and North and South America) have angles up to 180 deg west. For inputting to the satellite dish pointing calculator, longitude west figures need to be input as negative numbers.
Decimal and degrees/minutes/seconds notation:
Maps and GPS receivers show latitude and longitude angles. Maps usually show bold lines marked in degrees (whole numbers) plus possibly intermediate lines marked 15, 30, 45 minutes or 10, 20, 30, 40, 50 minutes. GPS receivers typically show degrees plus minutes and decimal fractions of a minute. e.g. 45 : 23.1234 You can normally alter the display options on a GPS using the setup menu.
Each degree can be subdivided into 60 minutes (and each minute into 60 seconds for very high precision).
In cases where the map (or GPS readout) is in degrees and minutes, you need to convert the minutes part to decimal parts of a degree, by dividing the number of minutes by 60, so for example.
50 deg 30 minutes north = 50.5 degrees
45 deg 10 minutes east = 45.1667 degrees
92 deg 45 minutes west = -92.75 degrees
http://www.satsig.net/lat_long.htm
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