How is latitude expressed

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. Geospatial Activities.

Latitude and Longitude When we describe the Earth in spherical coordinates it is called Geographic, or Un-projected. This last example of coordinates is commonly used when reading a GPS and the second numbers Let's take a look at latitude because it is the easier of the two examples.

That is because there are approximately 69 miles between degrees of latitude rounded down to 60 to make the examples easier. In order to get from That is where that second number comes into play. We have reviewed two formats that coordinates can be given in, but there are actually three.

Let's review all of them using the Empire State Building example. Actively scan device characteristics for identification. Use precise geolocation data. Select personalised content. Create a personalised content profile. Measure ad performance. Select basic ads. The E or the W following a longitude measurement indicate whether the degrees are measured east or west of the prime meridian.

Minutes and seconds sometimes follow latitude and longitude measurements to more accurately pinpoint a location. Each degree can be divided into sixty minutes, usually indicated by a single quotation mark ex.

Each minute can be divided into sixty seconds, indicated by a regular double quotation mark ex. In the Northern Hemisphere, latitude can be determined by the angle of the North Star Polaris from the horizon.

The North Star always sits over the North Pole. Here, if a person looks straight ahead towards the horizon, the star would be directly overhead, creating a 90 o angle; thus the latitude at the North Pole is 90 o N.

At the equator looking north, the star is in the same direction as the horizon, so the angle between them is 0 o , and thus the equatorial latitude is also 0 o. At any other point in the Northern Hemisphere, the angle between the horizon and the star will give the latitude. Early mariners used an instrument called an astrolabe to calculate this angle.

Later the sextant was developed, which allowed more accurate measurements Fig. There is no direct analogue to the North Star in the Southern Hemisphere that is useful for determining latitude. However, the Southern Cross and Centaurus constellations can be used to find the south celestial pole. If a line is drawn through the long axis of the Southern Cross, and another line is drawn between the two brightest stars in Centaurus, the two lines will intersect at the south celestial pole.