Navigation

TWO SAD JOKES Who leaves the table after everyone’s eaten? –A cannibal. Why is the banana the most popular fruit? –Because it has appeal.

How do we know where we’re at? You are here. Huh? X

Before GPS…. Celestial navigation The pattern of stars and planets seen from Earth are constant in space. The celestial sphere. It is useful to be able to precisely specify positions on the celestial sphere. So, a set of coordinates is used that is similar to latitude and longitude on the Earth. The system of latitude and longitude was first suggested by Hipparchus, a Greek astronomer in the 2nd C. B.C. Hipparchus

The North Celestial Pole is the point on the celestial sphere directly above the Earth's North Pole. Similarly, the South Celestial Pole is directly above the Earth's South Pole. The star Polaris, in the constellation Ursa Minor, is located very close to the North Celestial Pole. Polaris is therefore also called the North Star.

More accurate: Longitude & Latitude Longitude: Angular distance on the earth's surface, measured east or west from the prime meridian at Greenwich, England. Lines of longitude are blue (east) and red (west) in the drawing.

Latitude The distance north or south of the earth's equator. 0 degrees latitude is the equator, the "belt" that goes around the "waist" of the earth. 90 degrees north is the North Pole and 90 degrees south is the South Pole. Lines of latitude are blue (north) and red (south) in the drawing.

Tools of the trade… Sexton: measures the angle between celestial bodies and the Earth to determine position. Compass: Point to magnetic North, so you can follow a course by knowing our position in relation to North. Loran C: radio transmissions from set positions on the surface of the Earth, that triangulate to give you a position. GPS: is a worldwide radio-navigation system formed from a constellation of 24 satellites and their ground stations.

Sexton a device that measures the angle between two objects. It uses the position of stars to find it’s latitude, longitude.

Compass

Loran C LORAN-C was originally developed to provide radio-navigation service for U.S. coastal waters and was later expanded to include complete coverage of the continental U.S. as well as most of Alaska. Twenty-four U.S. LORAN-C stations work in partnership with Canadian and Russian stations to provide coverage in Canadian waters and in the Bering Sea. LORAN-C provides better than 0.25 nautical mile absolute accuracy for suitably equipped users within the published areas. What is Loran-C? Loran-C is a low frequency/long wave electronic position fixing system using radio signals 100 KHz from 3 or more transmitters, linked in a chain. It gives a latitude and longitude readout position to marine, aero and land receivers.

The Global Positioning System (GPS) is a worldwide radio-navigation system formed from a constellation of 24 satellites and their ground stations. GPS uses these "man-made stars" as reference points to calculate positions accurate to a matter of meters. In fact, with advanced forms of GPS you can make measurements to better than a centimeter! In a sense it's like giving every square meter on the planet a unique address. GPS receivers have been miniaturized to just a few integrated circuits and so are becoming very economical. And that makes the technology accessible to virtually everyone. These days GPS is finding its way into cars, boats, planes, construction equipment, movie making gear, farm machinery, even laptop computers.

Coordinates given in Longitude, Latitude Longitude: 40 E Latitude: 65 N North South EastWest

Mapping activity od3fl5.swfhttp://olc.spsd.sk.ca/DE/k9mod/Mapskill/m od3fl5.swf