ORIENTEERING OBJECTIVES: - Learn to proper use a compass. - Find ones way without a map and compass. - Learn to proper use a compass. - Identify parts, symbols and meanings of contour maps. - Find ones way with a map and compass. - To get outside during a winter!!
DIRECTIONS WITHOUT A COMPASS: 1. Sunrise / Sunset March 21 & September 21: Exactly East &West at equator. June 21 (North of E & W). December 21 (South of E & W) 2. North Star (AKA Polaris)
DIRECTIONS WITHOUT A COMPASS: 3. Direction from the wind: Wind usually from the West in Minnesota. Cold wind from the North., Warm wind from South.
DIRECTIONS WITHOUT A COMPASS: 4. Direction from plants: a. Bark and growth rings thicker on north side of tree. b. Moss usually grows on the north side of objects. c. Shorter branches face prevailing winds. (W) d. Grasses grow away from prevailing winds.(E)
TRUE NORTH: A point where the earth rotates. (North Pole). Maps are drawn according to True North.
MAGNETIC NORTH: - All spinning object with liquid center have a magnetic field. - This point moves slowly over time. - Poles have actually reversed several times.
DECLINATION: *The difference between True North and Magnetic North *Zero degree declination line is from Hudson Bay through Florida
DECLINATION: Maps are drawn so that “True North” is at the top of the map. A compass only on the zero declination line points exactly north. Blaine Minnesota is 5 1/2 degrees easterly declination. East is least, West is Best
Compass Not Always Accurate!!! * Compass is useless at the North Pole.. (Even Seattle) 1. Sextant – Old way to use the position of the sun and the stars to determine your location.
Global Positioning System!!! GPS Satellites around Earth locate your position.
Global Positioning System!!! GPS Batteries may DIE!!!
PARTS OF THE COMPASS:
LATITUDE: Imaginary lines on the globe that run East and West. -Represent North and South. -0 degree at the equator -90 North is the North Pole -90 South is the South Pole
LONGITUDE: Aka: MERIDIANS: - Imaginary lines from North Pole to South Pole. -Measures East and West on globe. -0 runs through Greenwich England. (Prime Meridian) -180 runs through the Pacific Ocean.
BLAINE HIGH SCHOOL? W 93 15’ 48” N 45 11’ 56” ‘ = Minutes “ = Seconds
There are 60 Minutes in one Degree of Measurement. 60 Seconds in one Minute. (Not related to time)
MAP SCALES: A ratio between the map and the earth.
Large Scale Map Large Scale: Shows Detail 1: 12,000 1 inch on map = 12, 000 inches on the earth. (1000 feet)
Small Scale Map Small Scale: Covers a lot of area but it is does not show detail) 1 : 250,000 1 inch on a map = 250,000 inches on the earth
Different Series of maps One inch Area Depicted Series Scale Equals (Square Miles) 7.5 Minutes 1:24,000 2.000 feet 49 - 70 15 Minutes 1:62,500 Nearly 1 mile 197 - 282 Alaska 1:63,360 1 mile 207 - 281 U.S. 1:250,000 Nearly 4 miles 4,580 - 8669 U.S. 1:1,000,000 Nearly 16 miles 73,734 -102,759
TOPOGRAPHIC MAPS: Maps of high precision, showing rich detail of landscape. Woods, Clearings, Water, Man made objects, Elevation from Sea level)
CONTOUR LINES:
VOCAB TERMS BEARING: The direction stated in compass degrees. CARDINAL POINTS: The four principle points of the compass (N,S.E.W.) INTERCARDINAL POINTS: NW SW NE SE CONTOUR INTERVALS: Lines on a map that represent elevation above sea level. CROSS-BEARING: Two or more bearings which, when transferred to a map, indicates your location at the point at which they cross DECLINATION: The difference between Magnetic north and True north. Minnesota has an Easterly declination. The farther west one travels the more the declination is East.
VOCAB TERMS LANDMARK: A feature in the landscape which can be readily recognized. Anything from a prominent tree or rock to a church or a lake. ORIENTEERING: The study of using map and compass ORIENTING: Turning map in such a way that what is North on the map corresponds with North in the field. ORIENTATION: In general getting your bearings as to your location in the wild. PACE: A double step. RESECTION: Determining a location by cross-bearings from prominent landmarks. TRIANGULATION: The process of taking a resection to determine one’s location precisely.