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For the Home School ProgramBased on the Sunshine State Standards for Secondary Education established by

The State of Florida, Department of Education

PREMIER URRI ULUM SERIESPREMIER CURRICULUM SERIESREMIER URRI ULUM SERIESPREMIER CURRICULUM SERIES

Author: David H MenkeCopyright 2009

Revision Date:06/2009

Author: David H. MenkeCopyright 2009

Revision Date:06/2009

E RTH SCIENCE

TEXTBOOK

EARTH SCIENCE

TEXTBOOK

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INSTRUCTIONS

Welcome to your Continental Academy course. Progress through the course at your own pace, onelesson at a time. The textbook contains individual lessons that are listed in the Table of Contents.Additionally, each lesson is divided into various sub-topics. Important sentences and phrases are

highlighted in gray throughout the textbook. Bold print emphasizes important topics such as historicalfigures and events. Important information in tables and charts is bold and/or highlighted for emphasis.At the end of each lesson, practice questions and answers have been included. Use these to test yourmastery of each lesson BEFORE you complete the lesson assignment.

First, study each lesson thoroughly. (If you have the CD version of this course, you can print the entiretext book or one lesson at a time to assist you in the study process.) You should complete the lessonreviews printed at the end of each lesson and carefully check your answers. When you are ready, usethe ORANGE, 150-QUESTION ANSWER FORM to complete the open-book lesson assignmentquestions. Be sure to review the Things to Remember text for important reminders about the lessonyou are completing BEFORE you complete EACH lesson assignment. Work at your own pace and

finish the lesson assignments.

Once you have completed all lesson assignments in the course workbook, study the material in preparation to complete the proctored End of Course Examination. Remember, the proctored end ofcourse examination is closed book . Follow the instructions provided to you very carefully and besure to have a Proctor available before you begin the examination. Your Proctor, (an individual, whois at least 21 years old, not related to you and not a convicted felon) will observe you while you takeyour End of Course Examination to verify that you completed this test HONESTLY, without aid or inanyway violating the Scholastic Honor Code (see Student Handbook).

Use the RED, 100-QUESTION ANSWER FORM to complete the End of Course Examination.

When completed, place the RED ANSWER FORM AND the COMPLETED Test ProctorVerification Form (completed by the Proctor-NOT by the Student), the ORANGE, 150-QUESTION ANSWER FORM, and your Student Profile form in the Test Return Envelope.Affix sufficient postage and mail this back to our testing department (the envelope is pre-addressed). Be sure to indicate whether or not you are sending your PREVIOUS high schooltranscripts for evaluation on the Test Proctor Verification Form.

Students receive a percentage score for their course lesson assignments. The individual lessonassignment scores for a course are then averaged and translated into a letter grade, using a standardscale: 90-100% - A ; 80-89% - B ; 70-79% - C ; 60-69% - D ; below 60% - F. No individual coursegrade can be less than a D since all courses must be satisfactorily passed. In the event that a students

overall lesson assignment scores average out to less than a D, the student will be resent the CourseWorkbook to be completed again.

If the proctored end of course examination falls below 60 %, the end of course examination will beresent and will have to be repeated.FormT:06/2009

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EARTH & SPACE SCIENCE

3

About the Author

Dr. David H. Menke was born and raised in the St. Louis area. After high school, he enrolled at the

University of California at Los Angeles, and over the next eleven years, earned his two bachelorsdegrees, his four masters degrees, a teaching credential, and a Ph.D. in Science Education.

During his career, Dr. Menke has served as a public school teacher, community college instructor, anduniversity professor. He has worked full time at such institutions as California State University,

Northridge; Southern Utah University; Central Connecticut University; and Broward CommunityCollege. Much of his career was spent as an academic administrator of public observatories and

planetariums.

Dr Menke serves as the First Vice-President and COO of the International Planetarium DirectorsCongress, and as Chief Astronomer for the Sossusvlei Mountain Lodge in Namibia, Africa. As a worldtraveler, Dr. Menke has served as leader of many expeditions, including observations of eclipses and

comets on land and at sea. Dr Menke speaks, reads, and / or writes 16 languages.Dr Menke is married and has six children and 4 grandchildren. Dr Menkes wife is an elementaryschool teacher and mental health counselor.

Earth & Space Scienceby David H. Menke, Ph.D.

Copyright 2009 Home School of America, Inc.ALL RIGHTS RESERVED

For the Continental Academy Premier Curriculum SeriesHome School Program

Course: 2001310 1.0 Credits

Published by

Continental Academy3241 Executive WayMiramar, FL 33025

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TABLE OF CONTENTS

Forward4

Lesson 1 Earths Place in Space.7

Lesson 2 Geology35

Lesson 3 Meteorology.55

Lesson 4 Energy..91

Lesson 5 Technology.105

Course Objectives 117

Index..120

APPENDICES

Appendix 1 Glossary...122Appendix 2 Labs 131

Appendix 3 Solutions 153

Appendix 4 Scientists and Writers Involved in Earth & SpaceScience161

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It is common for scientists to make comparisons, and we use our planet, Earth, as a comparison.It is important to understand these values as we compare other celestial objects to Earth.

PLANETS

Distances between planets are measured in Astronomical Units (AU), The average distance fromthe Sun to Earth is defined as 1 AU.

Mercury

The closest planet to the Sun is Mercury, at a distance of only 0.387 AU. Mercury was namedafter a very fast-moving Roman god. He took messages from one person or god to another. The planet Mercury is fairly small, and it moves very fast in its orbit around the Sun at 122.5 km/s(about 74 miles/second).

Mercury is rather small. In fact, Earth is 20 times heavier.

Mercurys diameter is slightly more than one-third ofEarths diameter. Its day is very, very long. It spins on itsaxis in 58.6 Days! (Earth takes 24 hours). In addition,Mercury takes about one-quarter of a year (89 Days) totravel around the Sun Earth takes 1.0 Year.

Since Mercury is only 0.387 AU from the Sun, it receivesa lot more of the Suns energy than the Earth does 6.7 timesas much! And there is no air to screen out the powerfulsolar rays, so you could get a sun tan in just a few momentsthere. With no air, its air pressure is 0.0 ATM.

The force of gravity on Mercury is about 1/3 of what we have on Earth. That means that a personwho weighs 120 pounds on Earth would weigh 40 pounds on Mercury. And Mercurys surface iscovered with mountains, valleys, hills, craters, rocks, and similar stuff. Since it is a solid planetwith a hard surface, it is one of theTerrestrial planets i.e., Earth-like (since it is a rock, in theshape of a ball).

Mercury can become quite bright in our evening skies, but its position is so close to the Sun mostof the time, its very difficult to find it. The best times would be shortly after sunset in thewestern sky, or just before sunrise in the eastern sky. Mercury has no moons. Mercury has a carnamed after it.

Venus

Venus, another Terrestrial object, is the second planet from theSun. It is almost the same size as Earth, and it has about the samegravity. However, it is vastly different. First of all, it is 0.67 AU

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from the Sun, so it should be hotter. And it is hotter, but much, much hotter than expected! Theair temps are around 1000 degrees F. In addition, the atmosphere on Venus is very oppressive(hot, heavy, dangerous). In fact, on its surface, Venus air pressure is about 100 times that ofEarths air pressure about ton per square inch! The atmosphere is made of carbon dioxideand poisonous gases and acids like sulfuric acid, hydrochloric acid, and other foul things.

Imagine walking around on the planet Venus. First, the air pressure is so great that youd becrushed as flat as a pancake. Its so hot, that youd broil and would look like fried chicken. And,finally, the air is so toxic, that one breath of the air there, and your lungs would look like you had been smoking for 10,000 years! Venus is not a very friendly place. The only way you couldwander around would be to wear a special submarine similar to a bathyscaph.

Venus, named after the Roman goddess of beauty, takes about 2/3 of a year (225 days) to orbitthe Sun, and it spins on its axis in 247 days. Its the only planet whose day islonger than itsyear! Plus, it rotatesbackwards compared to the other planets!

Long ago, people believed that life flourished on Venus, and that it was like a Garden of Eden

with lush vegetation, many animals, and large underground deposits of oil. Well, that idea wasdestroyed when we sent spacecraft there to find out.

Venus is very easy to see with the naked eye, as its the brightest object in the sky next to theSun and the Moon. While Venus is also near the Sun in the sky, it does move far enough away to be seen easily after sunset on some evenings, and before sunrise on some mornings. Venus hasno moons.

MarsMars, also a Terrestrial planet, is further out from the Sun than Earth . In fact, Mars isabout 1.5 AU from the Sun. This means that it receives less solar energy, and should be cooler,than Earth. It is.

Many books have been written about possible people, andcities on Mars (Edgar Rice BurroughsCaptain John Carteron Mars; Ray Bradburys Martian Chronicles; H.G. WellesWar of the Worlds; and a movie calledTotal Recall, just toname a few).

We have sent numerous spacecraft to Mars. As result, wehave found out that, just like Earth and Venus, Mars doeshave air. However, the air on Mars is very thin, with an air pressure at its surface of about 1/100th that of Earths. Andmost of the air is carbon dioxide, not oxygen. So, we cant

breathe the air there, either.

If you decided to take a stroll on Mars, youd need to wear a space suit. A pressurized space suit.And it would have to be heated. For, with such low air pressure, you couldnt breathe, and your body would expand and eventually explode, if you didnt have a space suit on. The airtemperatures there are also really cold most of the time. However, sometimes it may reach ashigh as 80 degrees Fahrenheit, at the equator, on a summer afternoon. But the air wouldnt hold

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Jupiter is more than 5 times farther from the Sun as Earth. As such, its solar energy is less than4% of what Earth gets. But Jupiter has its own internal energy. The planet is shrinking, andgetting hotter inside. In fact, Jupiter has internal temperatures over 10,000 K. No matter that thetemperatures at its cloud tops are way below zero F.

Jupiter is made of hydrogen, helium, methane, ammonia, and other gases. Whereas Mercury,Venus, Earth, and Mars are labeled asTerrestrial planets, there are four planets that are likeJupiter; in other words, they are the Jovian planets.

Because of its composition, Jupiter is very similar to the Sun, or any other star. In some respects,Jupiter is a mini-star. However, there is no nuclear activity on Jupiter, so it is really a proto -star,i.e., an object that exists before it becomes a star. Jupiters mass, while about 318 times that ofEarth, does not have enough stuff to cause it to become a nuclear burning star. It will remain a proto-star forever.

EXAMPLE

If you were to travel to Jupiter and wanted to land on the surface of this giant world, yourspacecraft wouldnt land. There is no hard surface. Instead, you would continue for over 1000miles (1600 kilometers) before noticing anything more solid than its gaseous atmosphere. In theend, youd get stuck in a gooey mixture near the core, and then burn up.

It takes Jupiter almost 12 Earth years to travel around the Sun - 11.86 Earth years to be exact.Thus, a Jovian year is 11.86 Earth years. However, Jupiter rotates in less than 10 hours ascompared to Earths 24 hours. Thus, its day is 9 hours and 50 minutes. And Jupiter has a verythin ring around it.

Saturn

Saturn is also a Jovian planet, and the 6th planet from the Sun. It is about 9.5 AU distant from theSun, and is almost as large as Jupiter. However, it is not very dense. While Jupiter is 1.3

grams/cc, Saturn is 0.7 g/cc, which means thatSaturn could float in water if it were allowed to.EXAMPLE

If a large enough bathtub could be found to putSaturn in it, the planet would float, as it is lessdense than water. However, when you drained thetub, it would leave a ring.

Saturn has 23, or more, moons. Titan is thelargest, and astronomers and NASA haveextensively researched it. This large moon has anatmosphere rather rare for moons.

Saturn is also named for a god of the past. The Roman name is Saturn, but the Greeks called himKronos, and he was the father of the Olympian gods. Now there is a car named after it.

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Saturn takes almost 30 years to travel around the Sun, and its day is about 10 hours and 11minutes. However, you cant land on Saturn, either. Its just a big ball of gas like Jupiter.

The greatest attribute about Saturn is its huge ring system. Made of rocks and ice, these chunks

orbit Saturn in several different rings. Perhaps a moon wandered too close to Saturn, and wastorn apart by Saturns strong tidal forces.

Uranus

The next planet out, Uranus, is an interesting entity. At almost 20AU from the Sun, it is colder than a zombies heart out here.This big gas planet is about 17 times as heavy as Earth, butlighter than Jupiter or Saturn. Even so, Uranus is a Jovian planet.Uranus has 15 moons that we know of. The planet has a lot ofammonia and methane. It takes 84 years to orbit Sun, and its day

is about 16 hours. Many jokes are made about Uranus. TheBritish-German astronomer, Sir William Herschel discovered it,in 1787. In 1977, astronomers discovered that Uranus, too, had athin ring around it.

Uranus was named for a minor god of ancientRome. At first, William Herschel wanted to name itGeorgius, in honor of the King of England. Butscientists rejected that, and named it Uranusinstead.

Neptune

What is the only planet that makes music? The answer to this joke is Neptune, as it has atune. Neptune, another Jovian world, has a thin ring around it, too. Most of the time Neptune isthe 8th planet from the Sun. However, for about 26 years Neptune was the farthest planet fromthe Sun, as Pluto came closer to the Sun for a while. Neptune is about 30 times further from theSun than Earth. It is very cold. Neptune is a large gas giant, about 15 times heavier than Earth.

Made up of a lot of methane and ammonia, this huge world looks bluish-green, and it has 8 moons that we know of. It takes over 160

years to orbit Sun.At the time that Neptune was discovered, in 1864, it was believedthat it must be the final and last planet. Thus, it was given the nameof the god of the sea, Neptune. The Greeks called him Poseidon, butits the same guy. In mythology, the son of Neptune is Triton. In theDisney movie,The Little Mermaid, the father of Ariel, the mermaid,is Triton. In reality, Triton and Ariel are the names of two of Neptunes moons.

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Pluto

Named for what many believe had been a Disney cartoon dog, Pluto was really named after theRoman god of the underworld or the god of hell. The Greeks called him Hades. However, atthe Royal Greenwich Observatory in England, there is a color slide of Disneys Pluto in the

eyepiece of one of their telescopes. They have quite a sense of humor!As Pluto is the most distant planet, at an average of 39 AU from the Sun, any atmosphere on itwould be frozen into a type of ice. Pluto has one moon, Charon, which is almost as large asPluto. However, Pluto is rather small - smaller than our own Moon! It takes 247 years for Plutoto orbit Sun, and it rotates on its axis about every 6 days. We could land there and feel solidsurface, but there is very little gravity even less than on our Moon.

Comets

The dregs and refuse of the Solar System include the comets aword in Greek that means hairy, as in a person who needs ahaircut or a shave. There are virtually millions of comets orbitingSun, and only a few get close enough to Earth for us to see them. Arecent comet, named Macholz 2004, was discovered by anastronomer named Macholz. It graced our skies in late 2004 andearly 2005. While Comet Macholz was not as spectacular as othercomets, such as Comet Halley (1986) and Comet Hale-Bopp (1997),it was still a fun thing to observe.Comets are nothing more than dirty snowballs, traveling in very elongated orbits (not circularorbits like the planets). After several cycles around the Sun, the comets disintegrate and vanish essentially, they are built to fall apart, like Alka-Seltzer.

Meteors

Nothing more than flash of light meteors are quiteinteresting. Comets may remain in the sky for days orweeks, but meteors shoot across the sky in secondsand are then gone. Meteors are the visualmanifestation of meteorites rocky debris left overduring the formation of the Solar System. Meteoritescome Earthward due to Earths gravity. The wordmeteor means high in the sky, which is where wesee them.

As they approach Earth, they begin to burn up in the Earths atmosphere. Most of them neverreach the ground, but a few do. The largest meteorites can create huge holes in the ground, likethe one in Northern Arizona known as theMeteor Crater. It is near Flagstaff, Arizona.Meteorites are made of iron, or rock, or both.

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Asteroids

The word asteroid means star-likeand the first one was discovered by theItalian Astronomer Giovanni Piazzi on

January 1, 1801. However, asteroidsare not like stars at all. In fact, they aremuch more like planets, thusastronomers call them planetoids orminor planets. Piazzi at first hadthought he observed a star, so that iswhy he labeled them asteroids.

Asteroids orbit Sun in their ownorbits. A large group of them is between Mars and Jupiter and this group is called the AsteroidBelt. The largest asteroid, Ceres, is located there. There are a few other groups here and there.

However, while some people think that there used to be a planet between Mars and Jupiter, itwas never large enough. In fact, if you were able to glue all the asteroids in the Solar Systemtogether, our Moon would still be 20 times heavier.

Moons

Natural satellites, also knownas moons, orbit most of the planets, and a fewselect asteroids. A moon is just a natural type of asteroid or large meteoroidthat orbits a planet. Mars has two small moons that used to be asteroids. Jupiterhas 16 or more; Saturn has 23 or more. Uranus and Neptune have 15 and 8respectively or more. And Pluto has a small moon. That makes at least 67

moons, not counting those that orbit asteroids, in our Solar System. And many more moons arediscovered each year. There may be as many as 100 or more.

There are several moons larger than our Moon: the largest four of Jupiter (Io, Callisto,Ganymede, and Europa) and the largest one of Saturn (Titan), to name a few. The next chapterdiscusses our Moon in more detail.

Key Concepts Star Planet Moon

Comet Meteor Asteroid Names and information about the major planets

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Problems1. What is the name our star?2. What is name of the family of our star?3. How did each planet get its name?4. Which of the Terrestrial planets is the hottest?

5. Which planet is the largest?6. What are the leftovers of the Solar System?

THE MOON

(During this lesson, do Lab 2: Phases of the Moon)

Our larger natural satellite is called theMoon, and many things derive their namesfrom this bright orb of the night. The official

name of the Moon is Luna, just as Earthsname is Terra, and Suns name is Sol.

EXAMPLE

The word month comes from Moon, asthere was a new Moon every month.Menses also comes from Moon, asfemales have their menstrual cycle everymonth.

Our Moon travels around Earth once every27.3 days. However, since Earth is alsomoving around the Sun it takes the Moonan extra 2.2 days to catch up with Earth so as to have the exact same phase as it did the month before.

The Moon goes through aseries of phases shapes every 29.5 days. It goes from a new moon(which you cant see, thus often called no moon,) to crescent to first quarter to gibbous to fullto gibbous to last quarter to crescent and back to new.

The origin of the Moon has several theories. One is that the Moon was once part of Earth, billions of years ago, but as Earth was spinning, it threw off a large chunk of molten (liquid)material, and that later formed Moon. It has been moving away from Earth ever since.

A second theory is that Moon formed from the same raw materials as Earth when the planetswere formed. And the third theory is that Moon formed elsewhere as a type of asteroid, but thenwandered too close to Earth, and it was captured, as the other moon, Toro.

Evidence from moon rocks that we brought back from NASAs visits to Moon seems to supportthe theory that Earth and Moon were formed about the same time from the same raw materials.

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Moon is about the size of Earth. While Earth is 4 times wider than Moon, it is 81 timesheavier. Our planet is denser than Moon, and thus, much heavier. The mass, size, and density ofthe Moon determines its acceleration due to gravity. Some people believe that the Moon has nogravity, in other words, that you would float if you were on the Moon. This could not befurther from the truth. The Moon does have gravity, and its gravity affects tides on Earth.

However, Moons gravity is less than that on Earth. In fact, the Moons gravity is 1/6th

thegravity on Earth. So, if you were to weigh 120 pounds on Earth, youd weigh 1/6th of that, or 20 pounds, on the Moon.

EXAMPLE

One way to look at how it would be for you on the Moons surface would be to understand howstrong you are on Earth. Lets say that you could jump 1 foot above the ground in your back yardon Earth. Since Moons gravity is 1/6th, you would feel six times stronger on the Moon. So, youcould jump, not just 1 foot, but 6 feet, above the Moons surface. And if you can jump 2 feethigh on Earth, you could jump 12 feet high on the Moon. A baseball field in a covered dome on

the Moon would have to be huge, since a typical ball player could hit the ball about half a mile!And a person could strap on wings and be strong enough to actually fly inside that dome,assuming air had been pumped into it!

If you wanted to take a walk on the Lunar surface, youd have a very interesting time. Youwould most likely bounce rather than walk. However, youd have to wear a pressurized spacesuit, since with zero atmospheric pressure, your body would expand like a balloon and thenpop. You wouldnt like to explode all over the surface, would you?

In the sunshine, the temperatures can reach as hot as 200oF almost as hot as boiling water. Andat night, the temperatures drop to minus 200oF thats 200 degrees below zero Fahrenheit. So,your space suit better be air conditioned and heated, too.

The Moon rotates in one month and orbits Earth in one month. As such, it always has the sameface towards Earth. We never see the back of the Moon unless we travel out behind theMoon with a space ship. An old poem goes something like this:

Oh, Moon, Lovely Moon with thy beautiful faceCareening through the boundaries of spaceI wonder oh wonder, deep in my mindShall I ever, oh ever, behold thy behind?

And thus, a poetic astronomer wondered if hed ever see the back of the Moon.

When the Moon hits your eye like a big pizza pie, thats amor, is the first line of a romanticsong performed by the late Dean Martin. Well, sometimes the Moon looks very large, when, inreality, it is always the same size. When the full moon is rising along the horizon, one can thencompare it to distant trees or houses, or other things. In this vein, it can look very large.However, when the Moon is full and overhead in the middle of a vast sky it looks small incomparison. So, the Moon never changes size, but it looks that way by illusion.

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The Moon is also the primary cause of tides on Earth. While the Sun is 440,000 times wider thanthe Moon, it is also 1000 times further away. The huge mass of the Sun does affect tides, but notas much as the Moon does.

Key Concepts

Natural satellite Luna and Moon Tides Phases of the Moon Theories of Moons formation

Problems1. Name the 8 phases of the Moon2. What are the three theories of the Moons formation?3. How many moons does Earth have? What are their names?4. How much would a 180-pound man weigh on the Moon?

STELLAR SYSTEMS

(During this lesson, do Lab 3: Constellations)

A variant on a familiar poem goes something like this:

Star light, star brightFirst star I see tonightI wish I may I wish I might

Aw, shucks, its just a satelliteWell, not every bright dot in the sky is a star. Many times people confuse planets with stars. But planets are much closer, and they look larger. Therefore, planets dont twinkle. Heres anothervariant on a poem:

Twinkle, twinkle little starI dont wonder what you areFor I surmised your place in spaceWhen you left the missile base

Now all the wondering that I doIs upon the price of youAnd I wonder what to thinkWhat youre costing us per twink

Stars twinkle because of Earths air. The light from distant stars reaches us as a single beam, andthe movement of Earths turbulent air causes that light to vibrate, or twinkle. If you were toobserve the stars from a space ship outside Earth, or from the surface of our airless Moon, thestars would not twinkle at all.

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As most people know, stars make up patterns in the sky calledconstellations . While thesestars may not be related to each other, from our vantage point, they may look like a Big Dipperor a Lion in the sky.

Stars are self-sustaining, nuclear-burning objects. Planets merely reflect the light of our star, theSun. But stars give off heat and light. In the center of each star is a powerful nuclear reaction:

4 1H1 = 2He4 + 2 + + E

where 4 hydrogen nuclei (protons) are fused together, in a chain reaction process, to form oneheavier nucleus, helium, and giving off a lot of energy, E. (There are also two anti-matter particles created, called positrons, 2 +).

This is the same reaction as an atomic bomb, more specifically, a hydrogen bomb, and it is a fusion reaction.

Our own star, the Sun, is doing this. And while it is doing this, it is losing mass. For, in this process, mass is lost. You see, 4 hydrogen nuclei weigh more than 1 helium nucleus, so wheredid the mass go? It became energy, by the process:

E = ( m) c2

Where in this case, m equals the lost mass, and c stands for the speed of light (it issquared here). While the surface temperature of a star, like the Sun, may be 12,000oF (6000K), the core of the Sun is 10 million degrees or more! Stars are just large balls of hot gas, so onecouldnt stand on the Sun, even if they could survive the heat.

So, the Sun, like every star, is changing vast quantities of hydrogen into helium every second.And the amount of mass lost and turned into pure energy in our Sun is the equivalent of about600 tons per second! Even at this rate, the Sun has been losing this mass every second, and hasfor 5 billion years; it will continue for at least 5 billion more years, and it doesnt even seriouslyaffect the overall mass of the Sun!

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Some stars are young, some are old, some are large and some are small. Stars come inall kinds of colors, depending on their age and temperature. Our Sun is a middle-aged yellowstar. There are red stars, orange stars, green stars, blue stars, violet stars, and many other colorsof stars.

The life cycle of a star (also calledstellar evolution) has a lot in common with the life cycleof a human. After our conception, it takes about 9 months before we are mature enough to be born. Once everything is in place (gas, dust, and gravity), it may take a billion years for a star to be born. Humans grow up and live, 75 years more or less. After a star is born, it grows a shorttime, then it may live about 10 billion years before beginning its final process to die. When people live a routine life, they naturally age, and then die. So do stars. At about 10 billion years,the hydrogen fuel inside a star runs low, and the star begins to convert helium gas into carbon.

This causes the stars core to shrink, but causes the outer layers to expand, making the star into avery large, but much cooler,Red Giant. Later, when helium runs low, carbon begins to bechanged into iron, and the outer layers expand out to forever, and disappear. What is left is avery small (about the size of Earth), hot star, called aWhite Dwarf.

Of course there may be people who die earlier than expected, perhaps from a tragic accident,war, or disease. Some stars can also die a violent death and explode.

Anyway, eventually most stars that live to become a White Dwarf merely burn out in a few billion years, leaving a cold, burnt cinder made of diamonds (compressed carbon). However,heavier stars may continue to shrink and become, first, rapidly rotating neutron stars (about thesize of a city) called pulsars, or, secondly, they continue to shrink until they become smallerthan a pinhead, and then rip a hole in the fabric of Space-Time, as in becoming a Black Hole,and then they disappear in time and space. No kidding.

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The closest star to the Sun,Alpha Centauri, is about 40trillion kilometers (25 trillionmiles) away. If you could travel

at the speed of light (300,000km/s), it would take over 4years to get there. Thus, AlphaCentauri is 4.3light years away, where 1.0 light yearequals 9.5 trillion kilometers(5.88 trillion miles). Using aconventional space ship, itwould take over 7 million years

to reach the Alpha Centauri star system. Wow.

About 60% ofstars are paired up with one or more other stars. Only 20% of stars have planets.The remainder are lone, single stars. Thus, some stars are binary stars, or have 4 or 6 stars intheir close proximity and orbit each other.There are also associations or clusters of stars, from a dozen to hundreds, or thousands, or evenhundreds of thousands or millions.

EXAMPLE -

The Pleiades star cluster has about 100 stars.

The globular cluster in the constellation Hercules hasabout 300,000 stars. The globular cluster in the constellationof Sagittarius has about 7 million stars. And there aremillions of clusters out there.

Key Concepts starlight twinkling stars nuclear-burning star

constellation star systems with planets binary and multiple star system

Problems1. What is the name of the closest star to the Sun?2. How far is the nearest star from the Sun?3. What is the speed of light?4. Describe the life cycle of a star.

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GALAXIES

As mentioned in the previous lesson, starsoften are parts of groups (associations orclusters). Well, there are super huge

groups of stars called galaxies. If a grouphas more than 1 billion stars, then it isclassified as a galaxy. Our Milky WayGalaxy has about 400 billion stars, and ourSun is but one of them!

Our galaxy is calledthe Milky Way. This is because the wordgalaxy comesfrom the Greek word galactos whichmeans milky way. Our galaxy containsabout 400 billion stars, and it also has two smaller satellite galaxies that go around it, just like

a moon orbits a planet! The larger of the two has about 10 billion stars; the smaller one has about2 billion stars. These galaxies are not visible in the Northern Hemisphere. They were discoveredhundreds of years ago by the sailing crew of Magellan. Thus, they are called the MagellanicClouds, in honor ofMagellans voyage, and because they look more like clouds to the unaidedeye than they do like galaxies.

In ourgalaxy neighborhood thereare at least 20 galaxies. The largest inthe group is called theAndromedaGalaxy. It has slightly more than our400 billion stars, and it is at a distanceof 2 million light years away makingit the nearest major galaxy to theMilky Way. Andromeda also has twosatellite galaxies going around it.

Galaxies come in different shapes and sizes, too, and they areat different distances. The closest galaxies are less than 2million light years away, while the most distant are about 20 billion light years away. The most distant objects that we seeare believed to be the nuclei of newly forming galaxies, and

we call them Quasi-Stellar RadioSources, or Quasars for short.

Our universe, called theUniverse, seems to be expanding,or getting larger. If it were theshape of a ball, its diameter might be 40 billion light years, or more.

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There are many types of galaxies: Spiral, Elliptical(oval), Irregular, Peculiar, and others. The largestgalaxies are Elliptical. The smallest galaxies are alsoelliptical in shape. Our Milky Way is a spiral galaxy.

Then there are the Quasi-Stellar Radio Sources(mentioned above) at the edge of space.Quasars, orQSOs, are the nuclei of newly forming galaxies up to 20 billion light years from Earth. Thus, ifwe could magically go to any one of them, they would not be newly-forming at all. They werenewly-forming 20 billion years ago! Thus, our Universe is about 40 billion light years indiameter. And what is beyond? That, my friends, is not defined!

Key Concepts Galaxy Types of Galaxy Quasar

Magellanic CloudsProblems1. Where did we get the name Milky Way for our galaxy?2. How many galaxies are in our local neighborhood?3. What is the largest galaxy in our neighborhood?4. What is a Quasar?

HISTORY OF FLIGHT AND SPACE TRAVEL

(During this lesson, do Lab 4: Planes and Rockets)Man has longed to fly since the beginning of time. However, humans are not built to fly well,at least not naturally. Thus, we have to find ways of doing it that are mechanical and such.

EXAMPLES

Long ago,Greek legend has it that an Athenian architect andinventor, Daedelus, made wings out of real bird feathers andwax. He and his son, Icarus, who had been held captive by anevil King, Minos of Crete, were then able to escape by flying

out of the prison. Daedelus and Icarus were successful atflying out of the dungeon, but Icarus wanted to fly higher,and when he got too high, the Sun melted the wax in hiswings, causing his wings to fall apart. Sadly, Icarus to fell tohis death. Too bad that he had no flight insurance.

In another story, there was once a Chinese scientist namedWan Hu. This was back in the time when the Chinese usedfireworks to celebrate their holidays. One day, Wan Hu

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decided that he could strap 47 rockets to his favorite easy chair and blast off to the Moon. Hereasoned that once he got to the Moon, he could fly home by waiting until the Moon was highoverhead, flap his little wings, and float safely back to Earth.

The day had come, and he had 47 assistants light all 47 rockets simultaneously while Wan Hu

was sitting in his chair. The roar of 47 rockets was deafening. There was much smoke. When thesmoke cleared, there wasnt a sign of Wan Hu anywhere. All legend says is that he went to visithis ancestors.

A Spanish scientist namedDomingo Gonzales decided to train a flock of geese to fly him to the Moon. He harnessed themaltogether, and connected them to a chair. The geese took off

with Domingo and he was never seen again.

There is also a legend that the famous French writer,Cyrano de Bergerac, decided to go to theMoon. He tried all sorts of methods, but none worked except his last one. He built an airplane-

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like object and flew up into the sky. He didnt land on theMoon, but in Canada instead. The Royal Canadian MountedPolice came out to see what the problem was, and theysupposedly helped Cyrano. They tied rockets to his airplane, and lit them. He blasted off from Earth and landed in

a tree upon the Moon. Later he floated back to Earth usinghis wings, but when he returned, no one believed him.

Science fiction writer , Jules Verne , wrote a book entitled De la Terre a la Lune (From the Earth to the Moon) in the1800s. In his book, he tells of three American astronautswho blast off in a rocket - called theColumbiad - from a base inCentral Florida. They safely travel to the Moonand later return, landing in the Ocean. A U.S. Naval vessel picks them up. That sure seems like it really happened but100 years later!

In reality, the first scientist to try flying was the Italian genius,Leonardo da Vinci, whoinvented, among other things, a flying machine that resembled todays modern helicopter. Whilehe designed and built this helicopter, it didnt work very well. He was able to fly it for a shortdistance before crashing. Fortunately, he survived the crash. Da Vinci also designed butnever flew a flying machine called theornithopter, which resembled a mechanical bird.This was the forerunner of the modern airplane. (The study of birds is calledornithology).

Floating balloons were another way for men to go up into the sky and fly. The first hot air balloon with human passengers lifted off the ground in 1783. Two brothers,Joseph and JacquesMontgolfier in France, built the balloon. Their balloon carried two people some 91 meters (300feet) off the ground.

Another Frenchman,Jacques Charles, created a hydrogen gas balloon, and although with no passengers, the balloon driftedfor two hours, and traveled a distance of 43 kilometers (about 27miles). Once men got started, they could not stop. Many moreadventurers began building and flying balloons often withthemselves in the basket suspended beneath the large gas-filled ball.

In 1785,Jean Blanchard and John Jeffries (an American),were the first humans to travel by balloon across the EnglishChannel from France to England. Meanwhile, 8 years later, thefirst balloon to go aloft in America happened at Philadelphia.

They wanted more air travel.In 1836 a huge hot air balloon traveled from London to Weilburg (Germany) in about 18 hours.It covered a distance of 800 kilometers (500 miles). Eventually the military got involved. In fact,during the war between France and Prussia in 1870, observers were sent up to spy on enemy positions. Armies in World War I (1914-1918) made extensive use of balloons, especially formilitary observation.

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Airships, also known asdirigibles, were large passenger balloons with space for many passengers. They usually had engines on them so that they could be steered. They were propelledforward by, well, a propeller, like on an ocean going vessel.

Henri Giffard, a French scientist, developed thefirst successful passenger airship in 1852. Otherssoon followed and by 1884 inventors and engineerswere creating new designs almost yearly. Theshapes of these aircraft were not round, like a ball, but, rather, elongated, like a cigar or pickle.

Count Ferdinand von Zeppelin was one of themost famous of airship builders. The Germaninventor successfully launched his first airship in

July 1900. Pilots could steer the ship rudders, and two internal-combustion engines, which

rotated propellers. Passengers, crew, and the engine were suspended below the balloon.German airship makers thought that they could make some money by creating airships for passenger travel. The first zeppelin airship, the Deutschland , began commercial airline servicein 1910. Even though the first successful airplane had been tested some 7 years before, airplanetravel for passengers was still far in the future.

Both French and German armies used airships (by this time, called blimps) during World WarI. It was determined through experience that blimps were way too slow, and too easy a target, to be used for attacking opposing soldiers. Therefore, they were limited to observation. After all, blimps could remain stationary in the air for long periods while the airplane could not.

After World War I, both the British and the Americans began building larger and larger blimpsfor travel purposes. However, the safety records were poor, and most ended up crashing.

Some of the early blimps used hydrogen gas, but in 1923, the U.S. Navy commissioned a large blimp using helium gas. This was a stroke of genius, since, while helium is four times heavierthan hydrogen, it is still very light, and the best part, helium does not explode. Hydrogen is verydangerous. Most party balloons today are filled with helium all done at a local grocery store!

Unfortunately, blimps do poorly in the wind, and in September 1925, the Navys blimp wasdestroyed in just such a weather event. But the Navy didnt give up. Even before its first blimpwent down, it had a newer, larger one, that carried 30 passengers including sleeping cabins! Inits 8 years in service, it completed more than 250 flights, including trips as far away as PuertoRico and Panama.

In 1928 the Graf Zeppelin came out, in Germany, and during its nine years of service, it crossedthe Atlantic Ocean 139 times, including a trip around the world with stops only at Tokyo, LosAngeles, and Lakehurst, New Jersey!

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Also in 1928, the U.S. Navy launched two new blimps, each with small bi-plane aircraft. Thesecould take off, or land at the blimp while a flight was in progress. There is an image of this inthe movie, Indiana Jones and the Last Crusade. But, again, these blimps were short-lived, too.By 1935, the United States gave up the pursuit of blimps for passenger travel.

The British tried to create some of the most fabulous passenger blimps, and it made two of them, both in 1929. These diesel-powered vessels were magnificent, with dining, sleeping, andrecreational facilities for 100 persons! Even so, storms wreaked havoc on blimps, and by 1930,Britain abandoned blimp travel. Of course, by then, the airplane had overtaken the blimp in faster and much safer travel.

The most famous blimp was the German-builtHindenburg built in 1936. It had made severaltrans-Atlantic crossings, but, as most people know, it wasdestroyed by fire in 1937 as it landedat Lakehurst, New Jersey. While some passengers and crew survived, 35 people on board - and 1crewmember on the ground were killed.

Since the destruction of the

Hindenburg, very few nations haveused blimps. However, the U.S.military still uses unmanned blimpsfor observation, communication, andweather.

Meanwhile, the airplane was makingitself known in the world. Manytried unsuccessfully - to makeflying machines, but only whenOrville and Wilbur Wright builtand tested their contraption in NorthCarolina in 1903 did the worldaccept the airplane as a real deal.

But before the Wright brothers had their success, there was a lot of history in the development ofthe airplane. Leonardo da Vincis ornithopter was mentioned above.George Cayley, a Britishinventor, began his design and research in about 1799. He studied da Vincis ornithopter, whichhad moveable wings, but decided to have solid wings that didnt move, and some type of deviceto move the airplane forward. In the end, he created a pretty good glider (like an airplane, butthere is no engine; it uses the wind and breezes to float from one place to the next). The firsthuman to travel successfully in a glider was Cayleys assistant a full 54 years after his firstdesign!

A French engineer namedClment Ader did the first manned flight of heavier-than-air plane 13years before the Wright Brothers . The airplane got airborne, but kept touching the ground onand off over a distance of 50 meters (160 feet). Thus, it was not designated as the first workableaircraft.

The one man that could have received the fame and glory for being the inventor of the airplanewas Samuel Langley. In 1896, he was able to create a very successful airplane and it flew

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extremely well. However, it had nobody on board. By the time he was able to make the changesto create a manned airplane to work, theWright Brothers had done their demonstration.

Airplanes at first were novelties, as were thehorseless carriages, or forerunners of the

automobile. The airplane was not recognizedright away for its commercial and militaryvalue.

During the very early 1900s before World WarI, airplanes made the county-fair circuit, wheredashing pilots drew large crowds - but few

business people. One interested client was Americas War Department. It had been using balloons as mobile observation posts over battlefields and it was interested in aircraft as early asthe Spanish-American War in 1898.

In September 1908 the Wright brothers demonstrated their latest version to the U.S. ArmysSignal Corps at Fort Myer, Virginia. During one demonstration, while Orville Wright wascircling the airfield there, the airplane crashed. Orville survived, but an on-board militaryobserver, a one Lieutenant Thomas Selfridge, died from his injuries a few days later. He becamethe first fatality from the crash of a powered airplane.

The first man to cross the English Channel in an airplane was the French engineerLouis Blriot. On July 25, 1909, he crossed the Channel in his own homemade airplane that he called theBlriot XI. Blriots feat convinced the world that airplanes would be very valuable in warfare.

The airplanes further potential was shown in 1910 when an American pilot namedEugene Ely took off from - and landed back on warships! Then, in 1911 the U.S. Army began testing theuse of airplanes to drop bombs, using a Wright brothers biplane.

Also in 1911, two other events occurred. First, an Italian military officer decided to fly over andobserve enemy positions during the Italo-Turkish War. Second, the American inventor and

aviator Glenn Curtiss built the seaplane. His biplanehad a large pontoon, or floating device beneath thecenter of the lower wing and two smaller pontoons beneath the tips of the lower wing.

One of the glorious years of flying was in 1913 whenaerobatics (also known as acrobatic flying) came out.This included flying upside-down, doing loops, anddoing other stunts that showed how maneuverableairplanes could be. Plus, several adventurous pilots

made long-distance flights that year, including a 4,000-km (2,500-mi) flight from France toEgypt (however, it was not a nonstop flight) and the first nonstop flight across the Mediterranean- from France to Tunisia.

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Because of national security in several countries, the advanced development of the airplaneimproved markedly. There were European designers, such asLouis Blriot, and Dutch-American engineers, such asAnthony Herman Fokker, who took the basic designs of theWrights and advanced them to make faster, more powerful, and highly accurate killing machinecombat airplanes.

Fokkers planes, which were used by German pilots, were considered better than used by theBritish. In fact, Fokker mounted a machine gun on the airplane in 1915 that had a timing gearallowing it to shoot bullets between the aircrafts rotating propellers! This was quite anaccomplishment! Fokkers resulting plane was the most successful fighter in the skies during thatera.

As during most war time periods, technology takes a front seat in developing military supportmaterials, and the airplane was no different.As a result, there was huge progress in thedesign and building of airplanes during World

War I. Some of the best British fighter planesincluded the Sopwith Pup (1916) and theSopwith Camel (1917). The latter has beenmade famous in the Charlie Brown cartoonstrip, by the pet dog that pretends to fly aSopwith Camel while atop his doghouse.

The Camel flew at 5,800 m (19,000 ft) andcould reach 190 km/h (120 mph). This was most amazing for the time. By the end of World WarI fighters had been made that could fly even higher - 7,600 m (25,000 ft) and could go as fast as250 km/h (155 mph).

Commercial flights those available for civilian use, began just 10 years after the Wright brothers first demonstration. The first regularly scheduled passenger flights anywhere in theworld were between Saint Petersburg and Tampa, Florida. I suppose those first air travelers preferred flying between these two cities, rather than driving the vast distance of 24 miles between them!

Regular commercial flights developed although slowly over the next 30 years. The growthwas driven by both the U.S. Postal Service, and by the two world wars.

The American inventorElmer Sperry perfected flying by instruments, rather than by sight, in1929. He created the artificial horizon and directional gyroscope. On September 24, 1929,JamesDoolittle (later known asGeneral Jimmy Doolittle during World War II) demonstrated that hecould take off, fly, and land using just instruments.

Boeing Aircrafts Model 247 of 1933 was the firstmodern passenger airliner.United Airlines ordered60 of these planes, which kept Boeing so busy, theycouldnt take other orders. As a result,Trans WorldAirlines ordered a similar type plane fromDouglas

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Aircraft. The final product was theDouglas DC-3. This particular aircraft was so reliable andsuccessful that there are still a few of them in operation even today!

Then, in 1940,Boeing developed theModel 307 Stratoliner, a pressurized upgrade of thefamous B-17 bomber. With a pressurized cabin, the Stratoliner could carry 33 passengers at

altitudes up to 6,100 m (20,000 ft) and at speeds of322 km/h (200 mph).

After World War II ended, and peace generally prevailed worldwide, airline companies such asUnited Airlines and Trans World Airlines, really began to take off, and prosper. New, comfortable, pressurized flights wereavailable in vast quantity.Aircraft that had beenused for military transport

were now available tocarry paying passengerson cross-country flights,and on trans-oceanicflights.

Wartime technology wason overdrive, creating the jet engine. Jets were usedin theKorean War forthe first time. Commercial

jet transportation began in1952 with Britains DeHavilland Comet, an 885-km/h (550-mph),four-engine jet. American manufacturers Boeing and Douglas developedthe 707 and DC-8, andPan American World Airways inaugurated itsBoeing 707 jet service in October 1958. Itwould seem that air travel changed virtually overnight. Jet service over the Atlantic allowed passengers to fly from New York City to London in less than eight hours. TheBoeing 707 carried 112 passengers and ended the propeller era. Jet engines need to squeeze and push air outof the back of the engines. No Air no thrust.

While jets are great for air travel over planet Earth, they cannot transportus to the Moon and beyond. We needed rockets for that. And for

rockets, we needed a rocket man.In spite of the earlier fireworks of Wan Hu and other Chinese, it was inthe 1920s, an American physicist and inventor , Robert Goddard ,developed the first rocket using liquid fuel propulsion engines. In 1923,he launched a successful rocket, a flight lasting 36 seconds, from hisAunt Effys cabbage patch in Massachusetts. All he got in return wasanger from his neighbors, and severe criticism from ignorant scientists.

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In 1930, Goddard moved his operation to New Mexico, and had several very successful launchesover a 12-year period. He developed a whole system with a launch pad, mission control, andother related things, but at the time, no one seemed to care.

World War II brought an increased interest in rockets, especially among the German scientists.

In fact, the Germans were quite successful at launching rockets towards Britain. When the warended, the US Army rounded up most of the German rocket scientists and moved them toAlabama to work on the new American Space Program. It was from there that the United Stateswas able to develop a rocket system that allowed humans to set foot on the Moon in 1969. Thefirst man to step foot on the Moon was a civilian scientists, Neil Armstrong. The second man, amilitary officer, was Buzz Aldrin. All total, twelve men, and no women, have walked on the

Moon.

After the Moon programended in late 1972,American scientists looked

for a way to develop long-term research from lowEarth orbit (LEO), andfrom the Moon. As such,they developed the Shuttle program, theHubble Space Telescope (HST), and theInternational Space Station(ISS). All of these are still inoperation.However, human destiny isthat one day we shallcolonize the Moon, the

planets, and perhaps, other star systems.

Key Concepts Early stories of flight and space travel Leonardo da Vincis inventions The history of balloons Early aircraft The development of the jet

Spacecraft

Problems

1. Who was Wan Hu?2. Who was Domingo Gonzales?3. What are the three gases often used in large balloons?4. The aviation inventor who almost came out with manned flight before the Wright brothers

was who?5. The first man to walk on the Moon was who?

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WAVES, LIGHT, AND SOUND

(During this lesson, do Lab 5: water waves)

The previous lesson discussed the history of flight and space travel. This is only one way to

gather information. Essentially, it is in situ forms of gathering information. We either sendhumans, or robots, out to some distant location, and the information is either brought back, orsent back via radio waves. Well, information may be transferred in waves of energy, which cancome in packets of energy, or packets of sound, or both. Information from space must come only

in packets of energy.

Lets first talk about what a wave is.Imagine going to the beach, and watchingthe water come in, and go out. Eachpacket of water is called a wave. And perhaps one wave comes to shore every 10

seconds or so. The wave is identified ashaving a high point, or crest, and a low point, or trough. The distance from thecrest of one wave to the crest of the nextwave is called the wavelength. In anocean water wave, that could be 30 feet

(about 10 meters).

The rate at which the waves arrive is called the frequency. For example, if one wave crestarrives at the shore and the next arrives 10 seconds later, and the next arrives 10 seconds afterthat, etc., then, every 10 seconds a wave arrives. As mentioned above, then, the frequency of thewave is one divided by the time, or 1/10 per second = one-tenth of a wave per second = 0.1 /second. This is also called 0.1 cycles per second, and some call it 0.1 Hertz, after a Germanscientist,Heinrich Rudolf Hertz, who studied waves in the late 19th Century.

Research has shown us that the velocity of a wave, v, is:

v = x

where stands for the wavelength (using the Greek letter,) and stands for frequency (using the Greek letter, ).

Examples-

Lets say that the distance from one crest to the other (thewavelength) is 3.0 meters (about 10 feet). Then one candetermine the speed, or velocity, of the wave, by therelationship of Velocity = wavelength x frequency = 3.0meters x 0.1 / second = 0.3 m/s (about 1 foot per second).

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One can also consider many other kinds of waves, includingwaving your hand to say helloto someone. As you wave at someone, you are moving your hand back and forth (probably leftand right), and each time you do that, you are completing one cycle. This takes no more thanabout 1.0 second in most cases, so the frequency would be one cycle per second. The length ofthe wave would be the distance from the left side, to the right, and back to the left side, around

60 centimeters (about 1 foot each way, or 2 feet total). Thus, one can find the speed of thewave, or how fast you are moving your hand, by using the above relationship:

v = x = 0.60 meter x 1.0 / second = 0.6 meter per second,

or 60 cm/sec (about 2 feet per second). Of course, its silly to find the speed of your hand whileits waving, but you get the idea.

Both light and sound come inwave packets, and each has a wavelength and a frequency. Plus,each has a speed or velocity.

The speed of light, using the symbol c is equal to about 300,000 kilometers per second (about186,282 miles per second). This number is a constant for all colors, all reference frames, and soforth. The different colors of light all have distinct, and different wavelengths withcorresponding frequencies, but all colors of light, from gamma ray to radio wave, have the samespeed. Please do not confuse radio waves with sound waves. They are quite different. Forinstance, radio waves (like light waves) travel through empty space at 300,000 Km/s, soundwaves cannot travel through empty space. They travel through different materials at differentspeeds.Example

Red light has a wavelength of about 6400ngstrms, whileblue light is much shorter, with a

wavelength of about 4000 ngstrms. Of course, at this point, we must ask, what is anngstrm? An ngstrm is a unit of length named in honor of a 19th Century Scandinavianscientist named AndersJonas ngstrm. It takes 10 billion ngstrms to equal 1.0 meter!However, some scientists prefer using a different unit called a nanometer. It takes 1 billionnanometers to equal 1.0 meter, so in that sense, 1.0 nanometer = 10 ngstrms = 10 . So, usingnanometers instead, red would be about 640 nm and blue would be about 400 nm. Astronomersuse ngstrms while physicists (not physicians) use nanometers.The relationship, v = x can also be used for light waves. However, instead of a speed thatcan change (v), we replace it with the constant speed of light, c:

c = x

Since the wavelengths of light are so incredibly small, it only seems to reason that thefrequencies of light are extremely large.

As mentioned, sound comes in wave packets, too. And sound has frequencies (sometimes calledpitch) from very high to very low. While the speed of sound is NOT a constant, itis constantwithin a volume that has the same temperature and density throughout. Why? Because soundwaves must travel through amedium , or in other words, sound must travel through a solid,

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liquid, or gas. It cannot travel through a vacuum. Most of us are used to sound traveling throughair, a gas. Therefore, air is the medium.

At the standard temperature and pressure (like room temperature and regular atmospheric pressure), the speed of sound, in air, is about 342 meters per second (about 1,100 feet per

second). Sound travels much faster in a liquid, like water, and even faster in a solid, like steel.Example

If you were to observe a thunderstorm, youd realize that first you see the bright bolt oflightning, then later, you hear the awesome rumbling of thunder. Since light travels so fast, yousee the bolt of lightning almost instantly. However, you have to wait for the sound of thethunderbolt to reach your ears, as it travels at 342 meters per second, not at the 300 millionmeters per second that light does. Therefore, if you see lightning, start counting the number ofseconds (use a stopwatch, or count, 1-Mississippi, 2-Mississippi, etc.) and when you hear thethunder from the lightning, multiply the number of seconds you counted by 342 meters (about

1100 feet). If you counted 5 seconds, then it would be about 1 mile away (about 5500 feet). Ifthis time span becomes shorter, this storm is moving toward you. One good thing: if youhear the thunderclap, the lightning bolt that caused it must havemissed you, because it is the lightning that can kill, not the thunder (no matter how loud or scary).

Key Terms and Concepts wavelength frequency velocity as a function of wavelength and frequency speed of light

speed of sound wave packet crest trough hertz ngstrm

Problems1. Who was Heinrich Rudolf Hertz?2. Who was Anders ngstrm?3. What is the frequency of a beam of red light whose wavelength is 6000 ngstrms?4. What is the speed of sound at STP? (standard temperature and pressure)5. If you see an ocean wave hit the beach every 8 seconds, what is its frequency?6. How long is a typical radio wave, which has a frequency of 560 kilohertz?

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LESSON 1 STUDY QUESTIONS

ANSWER TRUE OR FALSE. CHECK YOUR ANSWERS

1. There are five major planets in the Solar System.

2. There are only four minor planets; they are Ceres, Vesta, Pallas, and Juno.

3. Saturn is a Jovian planet, and the 6 th planet from the Sun.

4. Natural satellites, also known as moons, orbit most of the planets, and a few selectasteroids.

5. The light from distant stars reaches us as a single beam, and the movement ofEarths turbulent air causes that light to vibrate, or twinkle.

6.

If a group has more than 1 billion stars, then it is classified as a galaxy.7. The first man to step foot on the Moon was a civilian scientists, Neil Armstrong.

8. The distance from the crest of one wave to the crest of the next wave is called thewavelength.

9. Red light has a wavelength of about 6400 ngstrms.

10. Sound travels much faster in a gas than in a liquid.

ANSWER TO LESSON 1 STUDY QUESTIONS.

1. FALSE 6. TRUE2. FALSE 7. TRUE3. TRUE 8. TRUE

4. TRUE 9. TRUE5. TRUE 10. FALSE

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LESSON 2

Geology

In this lesson, you will understand what volcanoes are, and how they are connected toearthquakes and rocks. You will also understand rocks and minerals, as well as how thesurface of Earth fits together .

The lesson includes:

Volcanoes & the GeoChemical Rock Cycle

Volcanoes & Earthquakes

Rocks & Minerals

GeoMagnetism

Plate Tectonics

VOLCANOES & THE GEOCHEMICAL ROCK CYCLE

(During this lesson, do Lab 6: Make a Volcano )

Volcanoes instill terror in the hearts of men. However, they are a fascinating and important part of Earths geologic existence. Usually volcanoes occur near earthquake regions. Vulcanism,or the study of volcanoes, comes from the name of the Greek god of fire,Vulcan. This is not to be confused with a fictional planet called Vulcan from whence came science officerMr. Spock on Star Trek.

Volcanic eruption creates new land areas for animalsand many useful rocks and minerals. And volcanoes giveoff gases that help both plants and animals. Volcanoesare scary and can cause death and destruction, but theyalso provide the raw materials for life forms on Earth tosurvive and flourish.

GeoChemical RockCycle

To understand the science of geology, one must appreciate both volcanoes and the GeoChemical Rock Cycle and theirrelationship with each other. In this cycle, hot, molten (veryhot liquid) material beneath Earth (called magma) is spewed

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out by volcanoes and as soon as it hits the air, becomes lava. Some of the lava cools and becomes hard. This hard lava is now called an igneous rock.Some of these igneous rocks get washed away, and joins with other rocks. This combination ofseveral rocks into one is called a sedimentary rock, such as limestone. Other rocks combine,and under pressure, form a dense, heavy rock known as a metamorphic rock, such as some

granites. Then, over a long time, a few metamorphic rocks get heated under pressure, melt, andre-join the hot, molten material (magma) beneath Earths surface again. Thus goes the cycle.

Igneous

Igneous rocks include those that are composed of a host of different minerals that exist insideEarth.The minerals they are made of identify igneous rocks. Magma is mostly composed ofthe same elements that are part of the crust and mantle of Earth. These are silica (SiO2),aluminum (Al), iron (Fe), magnesium (Mg), calcium (Ca), sodium (Na), and potassium (K).Combined in various ways, these elements include the mineral quartz (SiO2), and the silicateminerals of feldspar, mica, amphibole, pyroxene, and olivine.

Quartz has the most silicon. Essentially, it is pure silicon dioxide. Another important mineral isfeldspar similar to quartz, but where theres much more aluminum and much less silicon.Feldspars also can contain potassium, sodium, or calcium.

Rock-forming minerals are composed of olivine, pyroxene, and amphibole. All three containsilicon and magnesium or iron - or both. All three of these minerals are often dark.

Dunite, another mineral, is composed of more than 90 percent olivine. After examining the morethan 700 pounds of Moon rocks that were brought back to Earth, it would seem that most Moonrocks are made of dunite. (By the way, a compound known asdunnite spelled with two ns -

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is an explosive named after an Army Officer in the U.S. Army the man who invented it Colonel Dunnite. Dont mix them up).Magma is a complex mixture of many elements. As it begins to cool, three main mineralscrystallize. The first is olivine. Once olivine crystallizes then the composition of the material thatused to be magma will be different it wont have much olivine left in it. As the temperature of

the magma continues to go down, other minerals begin to crystallize, such as pyroxene andfeldspar. Thismagmatic differentiation is an evolutionary process.

This process is repetitive until all of the minerals become solid. The final combination ofminerals formed is a function of three things: the original make-up of the magma, the way thecrystals separate, and how fast everything cools off.

Sedimentary

Sedimentary rocks are a mix of different rocks. Other rocks and minerals that had been formedelsewhere somehow all come together to form a new rock. Most of these items had been carriedaway by rain, glaciers, or blowing wind.

Sedimentary rocks are classified in one of two ways, asmechanical or as chemical. The mechanical designationsare rocks which fragmented and are created by thecrumbling of other rocks as they are bumped along theground by water. Some are eventually carried into largerrivers or lakes, where they are deposited in layers.Examples of mechanical sedimentary rocks include shaleand sandstone. Chemical sedimentary rocks are formedmuch differently. Rather than breaking apart, or beingcarried downstream, they are created by the evaporation ofcertain solutions of salts. Examples include gypsum andhalite.

Metamorphic

The oldest and most advanced rocks are known as themetamorphic rocks. That means that they change, as the wordmetamorphosis means. High heat and pressure have changedthese rocks, mostly from having been near and below Earthssurface.

Radioactive isotopes different versions of elements decayinto other elements, and as they do, they give off heat energy.Some of the heat within the earth is produced by the radioactivedecay of elements such as uranium, thorium, and potassium.

The hot magma from deep inside Earth provides energy to affect rocks, and metamorphose theminto something else. Then, there is also friction between rocks along earthquake fault lines that isanother source of heat.

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The immense pressures upon rocks accelerate texture and density variations. One of the unitsthat scientists use to measure pressure is thebar. One bar is equal to the amount of pressureapplied by the atmosphere to the surface of Earth at sea level. Wow. So what does that reallymean?

Pressure is defined as a force divided by anarea . Or, in math terms,

P = F / A

Where P is pressure, F is force and A is area. An area would be length multiplied bywidth, or

A = l x w

Where A is area, l is length, and w is width. Length has the units of meters (orcentimeters) and so does width. Therefore, area has the units of square meters (or square

centimeters). We often represent that as m2 (or cm

2).

Force is often used in the science of physics. The units of force are theNewton,or N, namedafter Isaac Newton. And the Newton is further broken down into a series of units: kg-m/sec2. Inour general system of units, we use pounds for weight, rather thanNewtons.Since this is not a physics course, just take the above on faith for now.

Since P = F / A, that would mean that pressure has the units ofNewtons divided by squaremeters, or N/m2. Another way to express pressure scientifically would be dynes/cm2. In this case,a dyne is a smaller unit of force, just like centimeter is a smaller unit of length.

Believe it or not, air has weight it exerts a force. If you are standing outside, at sea level, youhave a column of air, right over your head that extends for miles. All that air weighs something,and its pressure is squeezing down on you. So why arent you crushed? Because life forms onEarth have adapted to counter-balance the outside air pressure from within our life forms.

Just for your information, air pressure at sea level is about 14.7 pounds per square inch. In theterms used more by scientists, we dont use pounds or inches, but we use newtons (or dynes) andmeters (or centimeters). So, instead of 14.7 lbs/in2, we would say 103,000 N/m2 or 1,030,000dynes/cm2.

Meteorologists prefer using the termmillibar to describe the air pressure. Watch any TV

weather forecast, and the person is always saying, areas of low pressure, or areas of high pressure. On a statistical map, it would list the exact pressure inmillibars.

Well, 1,000 millibars equals 1 bar. Planetary scientists prefer the term atmosphere, so thatEarths air pressure at sea level is 1.0 ATM, or one atmosphere. That is just about the same as1.0 bar.

Now, back to rocks. Metamorphic rocks form under pressures of many kilobars, or thousands of bars (kilo means thousand). Rocks that are buried deep beneath many layers of rock

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experiencelitho static pressure, which causes the rocks to compress into a smaller, denser form.(This term comes from the Greeklithos, rock; and statikos, in place). Rocks at the bottomof a mountain (underneath the mountain) would be compressed into a very high density.

Density is the amount of matter squeezed into a volume. For example, water has a density of 1.0gram/cm3. As water, a liquid is much denser and heavier than air, so solids, like rocks, are muchdenser and heavier than water. Most surface rocks are about 3 times as dense as water. But somevery deep parts of the Earths core can have densities more than ten times that of water!

Thus, the combination of heat and temperature changes these rocks into metamorphic ones,although heat is the most important factor contributing to metamorphism. The melting points ofrocks vary from 650 C to 1,000 C (1,200 F to 2,000 F).

Metamorphism in local areas results from higher pressure and heat below Earths surface.These things occur as Earths crustal plates (we will cover these tectonic plates next) come intocontact with each other.

Most of the rock formed below Earths surface is igneous from cooled magma. However,subsequent deposits of rocks may bury some igneous and sedimentary rocks which hadoriginally formed on the surface.

These processes seem never ending. Thats because, well, they are never ending. Its a cycle ofastronomical proportion.

Key Concepts rocks minerals GeoChemical Rock Cycle

Lava Magma Igneous Sedimentary Metamorphic Pressure

Problems1. What is the difference between a rock and a mineral? Between a rock and a hard place? (just

kidding)2. What are the three primary minerals that make up rocks?3. Give an example each of an igneous, sedimentary, and metamorphic rock.4. What is the air pressure at sea level?

VOLCANOES & EARTHQUAKES

(During this lesson, do Lab 7: Earthquake)

This lesson is aboutseismology - the science of earthquakes. It is also closely connected tovolcanoes,as areas of activevulcanism and quakes often come together. It is rather common tohave a few earthquakes just before a volcanic eruption,

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Seismology involves the monitoring of natural earthquakes, and the study of artificialearthquakes that scientists set off. But we are getting a little ahead of ourselves.

The word seismology comes from two words,seismos, which is the Greek word that meansto shake or quake, andlogos, which is the Greek word for study of. Thus, seismology is the

study of shakes or quakes. That sounds logical.So, the word seism is another word for earthquake. A machine that senses earthquakesunderground is aseismometer. The machine that records earthquakes is aseismograph ( like anautograph). The graph that the seismometer draws on is called aseismogram (like a telegram).

Seismology is not limited to earthquakes, but alsoconcerns other celestial objects. We have been able todetectboth moonquakes and marsquakes, sinceneither of them can have earthquakes anyway. Someastrophysicists have speculated that out in space,

there are starquakes, galaxy quakes, and so forth.Even so, in this textbook we shall limit our conceptsas to how they are related to Earth. In fact,

seismology has opened vast understanding of the structure of the Earths core. Unlike the sciencefiction book of the 1800s by French author, Jules Verne(Journey to the Center of the Earth), our planet is quite different, and seismology has helped us find this out.

Whenever an earthquake occurs, it means that some hard and brittle part of Earths insides, evenmountain-sized underground rocks, has broken and slammed into another part of Earths insides.In some ways, the inside of Earth is like a bell. Not a very good bell, but a bell nevertheless. Forexample, when you ring a bell, it gives off one or more vibrating sounds. The metal part of the bell will continue to vibrate for a while, until it stops. The same is true of Earth. When a quakehappens, the solid, hard parts of Earth begin to vibrate. They do give off sounds, but humanscannot hear most of the sound frequencies.

While there are actually many different kinds of seismic waves produced by an earthquake, thetwo most predominant are the P waves and the S waves. Simply put, they are the primary (P)and secondary (S) waves. In more scientific terms, P waves are pressure waves that travel inrelatively straight (longitudinal) lines. These P waves can vibrate through solid, liquid, or gas.The S waves, sometimes called shear waves or shock waves, can bounce around a bit, and causeleft and right motion of the ground. However, S waves cannot travel through liquids (like theocean, or the Earths liquid core), or gases.

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Each of these two waves travels at different speeds. For example, P waves travel at about 8km/sec (5 miles per second), while the S waves poke along at a paltry 4.5 km/sec (2.8 miles persecond). This is a good thing, as we can get a very good idea when an earthquake occurred, and

how far away it was just by using astopwatch.

Once an earthquake begins, one will feel, ornotice, the ground going up and down. Theseare the P waves. They get to you first, as theyare fasterthan the S waves, and remember, both waves left the earthquake site at theexact same time. So, when you notice the upand down motion, check your watch, anddetermine the time as exactly as you can.Shortly thereafter, you will notice a left andright motion. These are the S waves. Once

again, note the exact time. Once you havedone this, you can subtract the two times,whether it be one second, 10 seconds, orlonger. Using this knowledge, there is amathematical formula that you can plug intothat will tell you how much time passed before the P waves hit you. Since P wavestravel at 8.0 km/sec, if the formula tells you10 seconds, then the earthquake happened 80kilometers from you, about 10 seconds before you felt the waves.

Now that you know the time of theearthquake and the distance, the only way you can determine its position is by either travelingalong a circle that is exactly 80 kilometers from where you were, to study the damage. Or to findtwo other people who did the same thing you did but at different locations. This is called themethod of parallax, or triangulation. Surveyors use it, as did George Washington.

Fortunately, scientists have set up automatedelectronic stations all over the planet, so onedoesnt have to use his own watch, and then run around hoping to find others who did the sameexperiment. But you get the picture.Once one is able to find the point of origin using triangulation, then one can study the area muchmore closely. Of course, earthquakes do not happen on the surface. They happen below theground often up to 700 kilometers (435 miles) down. The location on the surface that is theclosest point of the earthquake is called theepicenter. The actual location of where the quakehappened underground is called the focus.

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The Earths top layer of ground, and its notvery thick, is called thecrust. Earths crust is about 7 kilometers thick under the oceans, andnearly 50 kilometers thick under the largest mountain ranges. The crust that covers Earths globe

is a spherical shell, and like so many pieces in a complex puzzle, the crust is made up of a largenumber of these puzzle pieces. The pieces are calledcrustal plates , and divisions called faultlines separate the plates. More on this in lesson 5. However, as mentioned before, a sudden slipalong a fault produces both P and S waves.

At the bottom of the crust there is a division between the crust and the next level down, theupper mantle. The main research on this was done by a Croatian scientist namedAndrijaMohorovii in 1909 (Croatia was once part of Yugoslavia). Thus, scientists honored this man by naming the boundary after him. It is called the Mohorovi i discontinuity which means thereis a change in density. Most people often call it Moho for short.

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The damage caused by an earthquake dependson how strong it is (its magnitude) and howlong it lasts. It also depends on the location ofthe earthquake. For example, in the early1800s, a massive earthquake hit southern

Missouri. However, since virtually nobodylived there, no buildings were damaged, norany lives lost, it was not a human tragedy. Insome nations, building codes are very weak or non-existent. Thus, in even minorearthquakes, buildings can be destroyed andlives lost.

The strength of an earthquake is determined by how much energy it releases, and how muchdamage it causes. The earthquake Richter Scale was developed in 1935 by Professor Charles F.Richter (1900 1985) of the California Institute of Technology (CalTech). Richter was assisted

by German-born seismologistBeno Gutenberg, a colleague of Richters at CalTech.The Richter Scale generally goes from 1 to 10, where each step up signifies that the groundmoves ten times as much as the previous number. TheRichter Scale also allows for the amountof energy released, not just the distance that the ground has moved. For example, each step upsignifies a release of 32 times as much energy as the previous step.

Fractional numbers are also permitted, e.g., an earthquake of strength 6.4. A magnitude 4.3earthquake releases about the same amount of energy as released by the atomic bomb overHiroshima, Japan, in August 1945. That would also equate to about 20,000 tons of dynamiteexploding all at once at the same place.

The largest earthquakes in recorded history were about 9.5. That would be like dropping 66million atomic bombs on the same place all at once. While no earthquakes could conceivablysurpass the number 10, it is theorized that an earthquake of magnitude 12 would cause Earth tosplit in two!

The San Francisco earthquake of 1906 was a magnitude 7.9. The 1964 earthquake that hit Alaskawas 9.2. The San Fernando Valley (Los Angeles area) earthquake of 1971 was 6.6. The Northridge, California (Los Angeles area) earthquake of 1994 was a magnitude 6.7 earthquake.And there have been numerous others.

The Modified Mercalli Intensity Scale, or MMI Scale, is another way of measuring earthquakestrength. In fact, it is the most commonly used scale today. The MMI scale goes from 1 to 12,where 1 means barely detectable, to 12, which is total destruction.

Its amazing to realize that there are literally hundreds of earthquakes per day somewhere, oranywhere, in the world. Some areas are more prone to them, such as Turkey, Chile, and SouthernCalifornia. Very large earthquakes occur about every five years. Medium to strong quakeshappen once or twice a month. Some quakes also occur under oceans, which then creates hugewaves of water calledtsunamis, like the one that hit Southeast Asia on December 26, 2004.

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Quakes that occur between plates arecalled tectonic earthquakes. They arecaused by rapid release of energy storedwithin the rocks along a fault. The effect islike pulling a rubber band so tightly that it

snaps.On the other hand, volcanic earthquakesoccur near active volcanoes and are caused by the hot liquid magma rising to the top

of the crust, and pushing on it. Volcanic earthquakes occur in areas that have regular volcanicactivity.

Seismologists use a worldwide array of observing stations to keep track of what is happening,where, and how strong. The below-the-ocean earthquake of December 26, 2004 was tracked, butdue to poor global communications, the threat of a tsunami never reached the affected lands in

enough time to prevent the tragic loss of over 100,000 lives.Tectonic quakes are sometimes called interplate earthquakes, which happen along the boundaries between crustal plates. And there are some occasional intraplate earthquakes, too, that happennear centers of crustal plates. More on interplate and intraplate earthquakes will be discussed inLesson 2.5

Meanwhile when the ground shakes, it can cause landslides. This results in property damage, aswell as deaths of those near the falling structures. Even fires can break out and cause death anddestruction, not to mention the very awesome and frightening tsunami waves. Other negativeeffects may also occur, such as disease, starvation, dehydration for lack of clean water, and otherterrible consequences.

Perhaps one way to be safe from earthquakes is to reside in an area that has virtually no historyof quakes at all, such as Florida. But, then, you will have to contend with yearly hurricanes.

Key Concepts Seism Seismology Seismometer Seismograph Seismogram

P and S waves Fault lines Richter Scale Crustal Plates Volcanic and tectonic earthquakes Epicenter Focus triangulation

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Problems1. What are the two primary types of earthquake waves?2. What is the meaning of the Greek word seismos?3. Why cant the Moon have earthquakes?4. What large wall of water is often associated with under the ocean quakes?

5. What is the difference between the epicenter and the focus?ROCKS & MINERALS

(During this lesson, do Lab 8: Minerals and Rocks)

In Lesson 1 we learned about where rocks come from. Rocks are made out of minerals. Mineralsare combinations of one or more chemical elements which then create the substance. Examplesincludequartz, feldspar, olivine, pyroxene, mica, garnet, and so forth.

Quartz is the second most common of all minerals. Dont get it mixed up withquarts , which is a

unit of liquid volume that milk comes in.Quartz is composed of silicon dioxide, or silica, SiO2.It is found just about everywhere in the world, eitheralone as a lode of silica, or as parts of rocks. Quartzlooks and feels like a rock, but it is a mineral, whilerocks are combinations of several minerals.

Anyway, silica and silicate sound alike, but thedifference is that silica is only silicon and oxygen,where as silicate is a combination of silica with one ormore metals. Examples of silicates include olivine,feldspar, pyroxene, and others.

Quartz is a major part of granite, rhyolite, and pegmatite. These are igneous rocks. Quartz is also found

in metamorphic rocks, such as gneiss and schist. In fact, there is a metamorphic rock calledquartzite that is made of almost 100% quartz. While quartz is not a rock, quartzite is a rock.

Quartz forms striations and veins in sedimentary rock, such as limestone. Another sedimentaryrock, sandstone, is almost all quartz. Sand is mostly quartz, and expensive metal ore, such asgold, is often found mixed in with large amounts of quartz.

Quartz crystal can be found in huge chunks, or in tiny grains. Some are transparent, but all allowsome light through. In its pure form, quartz has no color. However, it is often found in differentcolors due to other stuff that is mixed in with it.

Heating a mixture of quartz (SiO2) and calcium oxide (CaO) also known as lime, makesordinary glass. No, not the lime fruit that grows on trees. This is the kind of lime one may use infertilizing soil. Bones and shells are mostly lime, or calcium oxide.

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Lead crystal, a beautiful and decorative type of cut glass, usedfor plates, glasses, vases, and so forth, is made of acombination of lead and quartz. Lead crystal is produced whenlead oxide (PbO) is substituted for lime in the mix. Thecomposition of lead crystal is 54-65% quartz, 18-38% lead

oxide, 13-15% soda (Na2O) or potash (K 2O), and other oxides.Such glass has a high refractive index, and creates lovelyrefractive colo

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