Expanding Horizons
An Historical Approach to the Future

 

LESSON PLANS created BY:

Jeff Kilmer
Clovereleaf Junior High
7500 Buffham Rd.
Seville, Ohio 44273
Email Nolrun@AOL.COM
Phone: (330)948-2500

 

Subject Area: Social Studies

Grade Level: 6-9

National Standards

Objectives

Estimated Time

Outcomes
Resources

Assessment

 

 

 

 

 

Introduction:

As the 20th century comes to a close, discoveries are being made that will forever change the way man looks at the universe. We are sending probes deep into interplanetary space to learn more about our solar system. We are mapping planets, studying the sun, chasing comets, and measuring near Earth asteroids. We are turning cameras back at ourselves to learn more about our own planet, and we are preparing for new voyages in the final frontier.

But man's interest in exploration is not new. In fact, it is as old as our beginnings; it is part of the human equation. Mankind is driven to explore--to find out what is over the next hill or around the next block. We call it curiosity.

Expanding Horizons will introduce you to scientists past and present, epic voyages of discovery, and the ways in which scientific discoveries fuel great voyages of discovery, exploration, and colonization.



Discoveries of the Mind Fuel Voyages of Exploration:

Did you ever wonder what prompted Christopher Columbus to sail to the west in search of the Indies? Was Columbus a man of rare hidden genius, or did his knowledge merely equal the knowledge of others?

Why is it that most of the great voyages of discovery occurred in a 30-year period between 1490 and 1521? What was the impetus that spurred these voyagers on?

Actually, only three things were needed to spur voyagers on to their great discoveries: accurate maps, navigational instruments, and ships.


Accurate Maps:

Renaissance:
During the Middle Ages,there were no accurate maps of the world for explorers to use. The early maps, which were called mappamundi , showed the Earth as a large flat circle with Jerusalem at the center. Paradise was at the top in the east. Europe and Africa lay north and south, with a great ocean encircling the entire Earth.

But in 1475, a book was published that changed the way Europeans looked at the world around them. Geography , written by a forgotten Greek astronomer named Ptolemy, was a collection of known geographical locations. Ptolemy made his observations at the height of the Roman Empire, but the knowledge was preserved only by the Arab nations. Its rediscovery was a boon to mapmakers, sailors, and fortune seekers everywhere. Geography contained no maps, but it included instructions for drawing maps of the entire known world using a grid system and coordinates. By following the instructions in the book, mapmakers created newer, more accurate maps of the world which depicted the Earth as round.

The round Earth theory was discovered by Eratosthenes about 200 BC. Using only his skills of observation and a basic knowledge of geometry, Eratosthenes made a surprisingly accurate measurement of the circumference of the Earth. Unfortunately, the round Earth theory and other scientific ideas were lost in time and not rediscovered until the late 15th century.

Armed with new, accurate maps and a grid system for recording their discoveries, explorers set sail in search of the fabled Indies and the great wealth they contained. Prince Henry of Portugal sent ships down the coast of Africa, remaining close enough to shore to see land. In 1487 Vasco DaGama rounded the Cape of Good Hope and sailed into the Indian Ocean, opening trade with India and East Asia. But Columbus, with Ptolemy's map as a guide, argued that the Indies lay only 3,000 miles west of Europe, a journey much shorter than the long, dangerous route around the horn of Africa. The frightening aspect of Columbus' proposal was that by sailing westward, the sailors and their captain would lose sight of land. Only a few years before, a vessel sailing out of sight of land was unthinkable. But new navigational inventions made Columbus' journey a bit less perilous.

Today:
In October of 1957 a message was heard for the first time from space from a satellite named Sputnik. Fired by the former Soviet Union, it was the first man-made satellite to orbit the Earth. Since that time many satellites have been put into Earth orbit to conduct scientific studies, including mapping our planet and the solar system. Shown below are several of the maps available of the Earth and the images from the solar system

The Surface of Mars: Olympus Mons

The Surface of the Earth: The Grand Canyon



The Surface of Io Jupiter's Moon







The maps shown above were gathered by satellites, which do much of the mapping done today.

The first image is of Olympus Mons, an extinct volcano on the planet Mars. Olympus Mons is the highest mountain in the solar system. The image was taken by the orbiting Viking probe in 1976.

The second image is the Grand Canyon as seen from a Landsat satellite. Landsat satellites study the earth for land use and track such things as global temperature and rainfall.

The final image is of the moon Io, which orbits the planet Jupiter. This photo taken was from the spacecraft Voyager 2 as it flew by the Jovian system. As you can see, Io is a world pockmarked with many volcanoes.

What differences do you see between the three images?

How has mapping changed since the days of Colmbus and the age of Exploration?


Navigational Aides:

Renaissance:
During a passage across the Atlantic, land would not be visible for days on end and some way of establishing his position was needed. Fortunately for Columbus, new navigational instruments were available during the later part of the 15th Century. The new instruments were the compass, the lead, the quadrant, and the log. As Columbus ventured out into the fitful Atlantic, he had these tools at his disposal.

The compass was made from a stone called lodestone, whose magnetic properties had been known for centuries and yet had never been used for navigation. As anyone who has experimented with magnets knows, magnetism can be imparted to iron. Armed with magnetized iron needles mounted on a pivoting base marked with the compass points, a navigator on a ship could always tell the direction the ship was headed. Every time a ship changed course the new heading was marked in the ship's log.

Knowing what direction you are heading is a valuable piece of information, but knowing only the direction is not good enough to plot your position east and west. You also need a way to keep track of the distance you have traveled as you sail in your ship. Distance equals the rate at which you travel multiplied by the amount of time you travel at that speed, often expressed in the mathematical formula D = R x T. Columbus kept track of the time he traveled through the use of an hourglass. Keeping track of time was easy - deciding how fast you were traveling was more difficult. Columbus used a device known as a log. It was simply a piece of wood with a rope tied to it. The rope had knots tied at regular intervals and the sailors would count how many knots ran out in a given period of time giving the speed of the vessel. Thus, a ship's rate of sped is still measured in "knots" to this day.

Once the position east and west was established it was still necessary to determine your position north or south. This was accomplished by the use of the quadrant. The quadrant was a device originally designed for use by astronomers to measure the angle of stars above the horizon. There was one particular star in the sky that was fixed in the heavens.This star is Polaris, the North Star. Astronomers and sailors had noticed that the angle of Polaris decreased the further south you traveled. By measuring the angle of Polaris, a seamen could determine his position north or south of the equator.

The only other danger to ships navigating the Atlantic was running into rocky shoals or coral reefs. A device similar to todays sonar was used. It was called the lead. It was nothing more than a lead weight with a rope attached and was thrown over the front of the boat to measure the depth of the water. Sometimes the lead was hollowed out and filled with tallow so that a seamen could bring samples back from the bottom of the sea.

These new navigational tools allowed Columbus to sail into uncharted waters and find his way not only back home, but also back to any lands he had discovered.

Today:

Today, navigating on Earth is a simple matter. Global positioning satellites, or GPS, can constantly update one's position anywhere on the Earth. Sonar signals probe the depths of the sea giving sailors better pictures of the ocean floor. Buoys mark dangerous shoals and and safe passages. Navigating in space, however, is much more difficult than any terrestrial voyage.

When navigating between Earth and the other 8 planets or 65 known moons in the solar system, one must keep in mind that in space everything is in motion. The moons, the planets, the sun, and all the other stars are constantly moving. As the Apollo 8 moon mission got underway, the moon was at a distance of 214 thousand miles from Earth and moving in orbit at a mean speed of 41 mph. Launching a spacecraft at a distant world is like trying to shoot a moving target with a rifle while spinning on a moving platform. Because of computer technology, we can achieve great precision in our navigation of the solar system.


Ships:

Renaissance:
The final item needed for Columbus to sail across the ocean were new ships. Developments in ship and sail construction created vessels that could brave the dangers of the stormy Atlantic. Between 1400 and 1450 new ships called full-riggers were developed. The ships were a combination of Mediterranean hull and an Atlantic rigging.

The Mediterranean hull had been developed for fighting battles. They were. These ships, called galleys, depended on the oarsmen for their propulsion. They were good in battle because they could travel very quickly in any direction because they did not depend on the wind. The hull design was very sleek and cut through the water very efficiently. Ocean going ships on the Atlantic, however, were sturdy ships designed to withstand the treacherous North Sea. They sacrificed sleekness for strength and so were painfully slower than the galleys.

What was needed was a marriage between these two vessels and ship designers began to do exactly that. Combining the sturdiness of the Atlantic hulls with the sleekness of the galleys allowed for faster ships with hulls that could withstand the pounding of the Atlantic.

Sail design also improved during this period. Atlantic ships had commonly used a square sail rigging which was particularly useful for sailing with the wind. The Mediterranean ships used a triangular shaped sail, called a lateen sail, which was particularly effective when sailing across the wind. When the ship designers of the 15th century put both sets of sails on a single ship, they developed a ship that could sail equally well with the wind or across a wind.

With these new developments in ship building, Columbus was able to sail more effectively in all sorts of winds and weather.

Today:
Today we are still developing new ways to travel in space. At today's prices it costs about 10,000 dollars to lift a pound of cargo into space. This is very costly and not very practical. NASA is working with its contractors to find ways to cut the cost of space travel. The space shuttle operation is already a more cost effective way of human space travel than was the old booster rockets, and with the development of the X-33 it may become possible for space flight to become just as routine as air flight.



Student Activities:

Language Arts:

1. Students can write a five paragraph essay comparing the ways in which maps were made in the past and the way in which we make accurate maps today. Students should use the Internet to gather information both on ancient maps and on Landsat Satellite data and how this is used to make detailed maps of the Earth.

2. Students can read Columbus' letter to Ferdinand and Isabella about his discovery of the Indies. How does Columbus use descriptive adjectives to make the lands he discovered sound like paradise? How does Columbus use persuasive writing techniques to convince the King and Queen to provide monies for another expedition? Finally, have students read comments from astronauts on Apollo 8 and Apollo 11 to mission control in Houston and compare their words to Columbus' letter.

3. Students can write two ship's logs, one from the point of view of a sailor aboard the Santa Maria as it slips out into the unknown, and the second from an astronau's perspective as he orbits the Earth in the space shuttle Atlantis. Students should use sensory details as did Columbus and Jim Lovell did on their personal voyages.

Social Studies:

1. Students should compare road maps, geographical maps, and topographical maps of a nearby large metropolitan city. Then students should look and landsat data on the same city using a cd-rom called "Cities Above" or NASA's "Cir C" cd-rom which contains NASA’s Pathfinder data and images. Using all of these maps how are land features, buildings, roads, and agricultural features represented differently in each map. What can maps tell us about land use, the growth of urban areas, temperatures, foliage, and weather?

2. Using landsat data from the internet, or a cd-rom, students can create an original map of their own using a grid system, legend, and scale. Students will need to determine what their map is designed to measure and code their map appropriately.

3. If new scientific theories fueled the explorations of Columbus, Magellan, and Cook, how do the discoveries we are making about the universe fuel our explorations?

Math:

1. Using the formula D=R*T students can be given word problems with rate of speed and time traveled. They can also be given the direction in which they traveled. Given a starting reference point students should keep track of their journey on the chart with any course corrections and places visited. They might also write about their journey and what they witnessed on the way.

2. Students can study the relationship between geometry and map making. All maps are geometric with a relationship to real places in the world. Using a graphing program and a spreadsheet, students can create topographical maps using a coordinate grid system to show changes in elevation.

3. Students can study the different angles of elevation for the sun throughout the year, keep a journal of its elevation on a spreadsheet, create graphs, and then write an explanation of the results.

Science:

1. Students can study the relationship between the magnetic field produced by the Earth and how a compass operates.

2. Students can study the movements of the star field and how the stars look in various elevations around the world using a program such as Red Shift. Why did ancient sailors use Polaris as a reference point for their quadrants?

3. Students can use satellite imagery to study various aspects of geology both on Earth and in space, or they could explore the deforestation of the rain forests using Landsat imagery.


Epilogue:

Everyone knows that the voyages of Columbus ushered in decades of discovery and exploration of the Earth. It should be exciting to students that today we are standing on the threshold of a new age of exploration.


Online Help and Information:
LandSat: NASA Pathfinder Homepage
Discover More About Ptolemy and Ancient Astronomers
Find out about Columbus and the land he discovered.
Check Out the Apollo 11 Mission to the Moon
Explore Maps with the US Geological Survey




NASA Glenn LTP K-12 Homepage
 
 
Please direct any comments to:
Web Related: Steven.Gutierrez@grc.nasa.gov
Responsible Official: Kathleen.Zona@grc.nasa.gov