Name:

INTRO TO NAVIGATION

1. the art and science by which mariners find a ship’s position and guide it safely from one point to another?

2. The and are located at the ends of the axis on which

Earth rotates. 3. What are Lines running through the poles and around the Earth called? 4. What is the great circle of the Earth that is equidistant from the North Pole and South Pole

called and cuts every meridian in half? 5. What are Lines that divide the globe into two equal parts, or hemispheres called? 6. What is the only great circle going around the globe from east to west? 7. What are the other lines that go around the globe parallel to, and north and south of the

equator called? 8. What is the significance of the great circle in navigation? 9. What is the distance around a circular area called? 10. Regardless of the size of the circle, what will always be the circumference? 11. How many seconds of arc are in 5 degrees of arc? 12. How is the Greenwich numbered and what is its other name? 13. What is the name commonly given to the 180th meridian?

14. is always measured east or west from degrees through degrees. 15. is always measured north or south from degrees through degrees. 16. Navigators mostly describe their location on the earth is terms of what? 17. One minute of arc measured along the equator, or any other great circle is called what?

18. Although a nautical mile measures about 6076 feet along the arc of a great circle, for most

problems in the Navy it is considered to be what? 19. 1° of arc at the Equator would equate to how many nautical miles?

20. How many nautical miles would there be in 6 degrees, 40 minutes of latitude? 21. How is distance on a chart measured? 22. What does the seaman’s speed term “knot” mean? 23. What are the four primary directions of the compass? 24. The direction the ship is facing? The direction the ship is steered through the water?

25. What is the name of the instrument common on larger ships which always points toward true

north? 26. Difference between magnetic and true north in degrees? 27. Where can you find the Earth’s northernmost magnetic pole? 28. If your ship was heading 080 degrees magnetic in a region where the variation angle was 10

degrees East, what would the true heading be? 29. The direction of an object from the observer measured clockwise from true north is called

what? 30. A ship is steaming on a course of 090 degrees at 15 knots. A lookout reports a contact bearing

090 degrees Relative. Where is the contact in relation to the ship? What is the True bearing of the contact? 31. How are objects seen by the ship’s lookouts reported? 32. What is a standardized drawing representing part of the navigable waters of the Earth called? 33. Water depts., obstructions, and buoys graphically displayed on a chart are called what? 34. What are persons who make maps and charts called? 35. What is the map and chart projection most commonly used by navigators or in a classroom

called? 36. Where is the greatest degree of distortion on a Mercator projection? 37. A curve on the surface of a sphere that cuts all meridians at the same angle and/or the path

taken by a vessel or aircraft that maintains a constant compass direction is called what? 38. If you were trying to locate your home on a map, place a circle around the scale map that would

be most useful: 1:1,000,000 or a 1:10,000? 39. If the scale of the chart is 1:12,000, what would one inch on the on the chart represent in feet

on the water? 40. Large-scale charts most commonly used to navigate and anchor in bays, coves, and rivers are

called what? 41. What type of charts are small-scale charts showing the approaches to large areas of the

coast?