1. The History of Navigation Created & Presented By : AbhishekGautam0737 KinshukPragyaJha 0701 ManinderThahal 0702

2. What is Navigation ? Navigation is the art of getting from one place to another, safely and efficiently. It is the process of reading, and controlling the movement of a craft or vehicle from one place to another. The first record of boats large enough to carry goods for trade is around 3500 B.C. and from this, navigation comes in the picture.

3. Brief Description A Brief description on the History & type of ships that has been used by the sailors on different time periods.

4. These first navigators stayed close to shore and navigated by sight of landmarks or land characteristics that they could see. Usually they traveled by day and sought a calm harbor or anchorage at night. They did not have charts but lists of directions, similar to today’s cruising guides. When they did venture out of sight of land, the navigator was able to determine his latitude (north/south direction) by observing the height of the sun during the day and the North Star at night.

5. History The first western civilizations known to have developed the art of NAVIGATION at sea where the Phoenicians, about 4,000 years ago. Phoenician sailors accomplished navigation by using primitive charts and observations of the sun and stars to determine directions.

6. Sailors of Ancient Times Egyptians were sailing as early as 2750 B.C. in papyrus boats. Greek sailors were learning more about India and England through wars and trading. Arabian, Chinese, and other cultures were also doing exploring and mapping before the European discoveries began.

7. Early Ship Building Techniques Ancient ship builders used a technique called Mediterranean whole moulding. There were three patterns used to make shapes, which were then cut directly from the timber.

8. Ships of Different cultures Egyptian Chinese

9. Ships from ancient cultures Its really thrilling, if we will plan our journey in these ships. Viking Greek

10. Sailors didn’t even have good tools to tell where they were going! Look at these old charts. They were not very accurate. No wonder ships often sailed off course! These were made over hundreds of years by sailors observing the land from the ship.

11. Sailors used nature to help them determine their location. With the correct tools, the sun, stars, and even animals could be very useful. Through this chart, we can see how sailors used the natural world to develop tools and skills needed for navigating their ships.

12. The red arrow is pointing to the North Star, which is also known as Polaris. Stars and other constellations helped sailors to figure out their position.

13. This is a quadrant. A sailor would see the North Star along one edge, and where the string fell would tell approximately the ship’s latitude. A sailor could also use this astrolabe. We lined it up so the sun shone through one hole onto another, and the pointer would show your latitude.

14. So what is latitude, and why was it important to sailors? Lines of latitude are imaginary lines running east to west on the Earth’s surface. 90 degrees 0 degrees 90 degrees The Equator is an imaginary circle around the Earth halfway between the North and South Pole. It is marked by the blue arrow on the picture. The latitude is 0 degrees on the Equator.

15. The Prime Meridian is marked on the map above. The blue and red line is showing a latitude scale. A Portuguese map maker was the first to draw the latitude scale using the Prime Meridian. Having latitude lines was a big help for sailors because they could tell how far north or south their ship was, but the tools they had were not always accurate.

16. The next thing that navigators worked on was a way to tell a ship’s longitude. This would allow them to tell their position east and west. (Remember that latitude was to tell position north and south.) The red lines are imaginary longitude lines that go from pole to pole. The Prime Meridian is 0 degrees longitude.

17. Mariners at this time also used the cross-staff and the astrolabe (c.1484 Martin Behaim) to measure the angle above the horizon of the sun and stars to determine latitude. The forerunner of the much more portable (and accurate) sextant, the astrolabe was used to measure the altitude of a sun or star. Heavy and clumsy, it was very difficult to use aboard a rolling ship, however, when new land was discovered and the astrolabe taken ashore, it was valuable in fixing the approximate latitude of the new discovery.

18. A major advance that made dead-reckoning much more accurate was the invention of the chip log (c.1500-1600). Essentially a crude speedometer, a light line was knotted at regular intervals and weighted to drag in the water. It was tossed overboard over the stern as the pilot counted the knots that were let out during a specific period of time. From this he could determine the speed the vessel was moving. Interestingly, the chip log has long been replaced by equipment that is more advanced but we still refer to miles per hour on the water as knots. Using the sun and the stars, the navigator knew his beginning and ending latitude – now he could determine the distance he had traveled to estimate his east/west position.

19. Sailors understood the idea of longitude long before they had a tool to measure it. Finally, in 1764, John Harrison created a very accurate chronometer, and this allowed navigators to figure out longitude while at sea.

20. British physicist Robert Watson-Watt produced the first practical radar(radio detection and ranging) system in 1935. It is used to locate objects beyond the range of vision by projecting radio waves against them. Radar can determine the presence and range of an object, its position in space, its size and shape, and its velocity and direction of motion. In addition to its marine uses, it is also used for controlling air traffic, detecting weather patterns and tracking spacecraft.

21. The hyperbolic navigation system knownas Loran (Long RangeNavigation) was developed in the U.S. between 1940 and 1943. It uses pulsed radio transmissions from master and slave stations that are received onboard and recorded as small waves on the screen of a cathode-ray tube. The distance between the waves corresponds to the difference in time between the arrival of the signals from the two stations. This difference is represented by a curve (hyperbola). Another set of loran transmitters repeats this process and position is determined by the intersection of the two curves called loran lines of position. Accuracy ranges between a few hundred meters and a few kilometers. Used mainly by US ships it is an expensive system with a limited coverage area and will ultimately be phased out in favor of a newer, more accurate navigation system called GPS.

22. GPS (Global Positioning System), initiated in 1973, is operated and maintained by the U.S. Department of Defense. This space-based radio-navigation system consists of 24 satellites and provides accurate positioning to within about 30 feet as well as velocity and time worldwide in any weather conditions. GPS works the same way as Loran (time difference between separate signals) but the signals come from satellites. Because you can receive GPS signals using small, inexpensive equipment it is being used in many new applications.

23. A quick look on the History.

29. Humans have always been curious. Some sailing was done because people wanted to explore new lands. Missionaries were interested for religious reasons. There were also those interested in finding gold, and other valuable goods. Trade became a very big reason to improve navigation. Explorers wanted to make money by trading, and by finding newer, faster routes to countries to trade with.

30. Well, we’ve seen that explorers have made progress over time. They have developed and perfected their tools and skills. We can always learn more about these ancient cultures by studying artifacts. This is why your research on the sunken ship is so important! Who knows what we will learn about the past from that old ship…

31. Thank You ! AbhishekGautam KinshukPragyaJha ManinderThahal