Latitude and Longitude D.Knauss RRHS 2009 Coordinates • The location of any object can be located by the intersection of two lines. • The Earth is divided into two sets of lines. Latitude Lines and Longitude Lines Longitude Lines • Longitude Lines run from the North to the South pole and are equal in length. They tell you where you are East and West of the Prime Meridian (runs through Greenwich, England). 0o longitude 30o East longitude 30o West longitude Longitude Lines • Looking at the Earth from above the North Pole, you can see the Prime Meridian and the International Date Line. 0o Prime Meridian 90o East 90o West 180o International Date Line International Date Line • The International Date Line sits on the 180º line of longitude in the middle of the Pacific Ocean. It is the imaginary line that separates two consecutive calendar days. - It is not a perfectly straight line and has been moved slightly over the years to accommodate needs of varied countries in the Pacific Ocean. International Date Line • Immediately to the left of the International Date Line (the date) is always one day ahead of the date (or day) immediately to the right of the International Date Line in the Western Hemisphere. So, travelling east across the International Date Line results in a day, or 24 hours being subtracted. Travelling west across the International Date Line results in a day being added. International Date Line and the Prime Meridian Not a Straight Line! Latitude Lines • Latitude lines run from East to West and tell you where you are North and South of the Equator. 90o North latitude 0o latitude (Equator) 90o South latitude Degrees, Minutes, and Seconds • Since the world is so big and there are only 360 degrees in a circle, the thickness of a 1- degree line could be the size of Rocky River! • Therefore, scientists have broken down the degree into smaller units which are based on units of time since the current time zone values are mostly based on Longitude lines. Degrees, Minutes, and Seconds • For every degree, there are 60 minutes • For every minute, there are 60 seconds • So, a very general location would look like this: 150o North and 30o West • A very detailed location would look like this: • 150o 15’ 35.4” North and 30o 25’44.4” West .