Third Grade - Science - Overview -April
 There are five lessons this month (Lessons 37-41) on astronomy, a subject that will be continued in the May lessons. Students demonstrate the movement of the Earth around the Sun, compare relative sizes of the planets and research a particular planet. They also create, transmit and receive a picture using pixel locations to demonstrate how satellites and space probes send pictures back to astronomers. They are given opportunities to work as a member of a group and independently.
 

 Third Grade - Science - Lesson 37 - Astronomy
 Objectives
Demonstrate movement of Earth around the Sun.
Distinguish between rotation and orbit.
Identify position of Earth during summer and winter in Baltimore.
Create a different picture for the Big Dipper constellation.

Materials
Picture of constellations for transparency (attached)
Dark-colored umbrella, white chalk, white paper, tape (see Teacher Note)
Adhesive label or tape marked "Baltimore"
Flashlight
Globe
Three-foot length of string with a roll of tape tied securely to one end
Worksheet (attached)
 

Suggested Books
Barrett, N.S. Night Sky. New York: Franklin Watts, 1985. Contains star charts and listings of constellations seen in the Northern and Southern Hemispheres.
Branley, Franklyn. The Big Dipper. New York: HarperCollins, 1991. Illustrates how the constellation changes its position and which stars make up the Big Dipper and its parent constellation, Ursa Major.
________. The Sky is Full of Stars. New York: HarperCollins, 1981. This Let's-Read-and-Find-Out Science book explains where to look for and how to identify constellations in the night sky. It also includes directions for making a box planetarium to project constellations on the wall of a darkened room.
Kerrod, Robin. The Children's Space Atlas. Brookfield, CT: Millbrook Press, 1992. Pages 54 through 68 highlight constellations seen in each hemisphere during different seasons of the year.
Krupp, E.C. The Big Dipper and You. New York: Morrow, 1989. This excellent introduction to stargazing focuses on one constellation and its importance to various cultures throughout history. The clever illustrations are outstanding. Pages 26 and 27 contain a good explanation of what causes the seasons.
Rey, H.A. The Stars. Boston: Houghton Mifflin, 1952. Rey has taken the arrangements of stars in constellations and redrawn them to more clearly show the sky pictures.
Stacy, Tom. Sun, Stars and Planets. New York: Random House, 1990. Pages 14 and 15 show the 12 constellations of the zodiac.
Stott, Carole. Night Sky. New York: Dorling Kindersley, 1993. Pages 18 through 27 show pictures of constellations and how to build a model of Orion.

Teacher Note
The inside of a dark-colored umbrella can serve as a night sky and show students how the constellations, with the exception of the North Star, appear to move. Using pictures of constellations from the transparency, draw them in white chalk on the inside panels of the umbrella. The North Star should be placed at the very top of the inside of the umbrella around the center pole. The Big Dipper's pointer stars should point to the North Star. Labels can be made with white paper and taped inside of the umbrella next to the constellations.
 

Reading Mastery IV, Lessons 119 and 140 include material about the Milky Way and the shapes of galaxies. Lessons 56 and 57 contain information on the solar system. Gravity is discussed in Lesson 63. For review of the solar system, see Openers, Level 3, Lessons 1 through 7.
 

A planisphere is a constellation finder that looks a little like a calorie counter. It consists of two disks of paper and a large window cut out of the front disk. One lines up the month, day and hour along the outside of the disk to reveal in the large window the constellations observable in the sky and their positions at that time. Simple planispheres are available at the Maryland Science Center's gift shop and at nature stores.

Procedure
Ask: When you look up at the sky on a clear night, what do you see? (dark sky, a sliver, crescent or full moon shining, many stars twinkling) Tell the students that when they look up at the sky, they are looking away from our planet Earth and out into space. The study of what is out there, what is beyond the Earth's atmosphere, is called astronomy. Write this on the board. Tell the students that early humans must have wondered about the sun, moon and stars that they saw in the sky. They must have wondered: What are those glowing, twinkling things up there? How far away are they? If I climbed a high mountain, could I reach them? Are they made of fire, of sparkling stones or maybe of gold? What makes them move around in the sky? Is the sky a huge bowl that covers the Earth? Are stars really lamps carried by gods to light their paths as they travel about the sky? Tell the students that for thousands of years, ancient astronomers watched the skies, searching for clues to the mysteries of the sun, moon and stars. They made maps of the skies and divided the stars into groups. They connected the stars in each group with imaginary lines to make pictures of people and animals that are called constellations. Write this word on the board.
 

Show the students the transparency of constellations or pictures of constellations from Suggested Books. Discuss whether the students see other pictures in the arrangements of stars. Tell them that different cultures saw different shapes in the arrangement of stars and gave constellations different names. Point out the picture of the Big Dipper or Drinking Gourd. Tell the students that a dipper is a long-handled cup used to scoop water out of a bucket. Tell them that other cultures saw the Big Dipper constellation as something else. The Vikings saw it as a wagon. The Egyptians saw it as a magic stick. The English saw it as a plow. The Chinese as a king's chariot. Native Americans saw it as part of a larger constellation in the shape of a great bear chased about the sky by birds. Tell the students that spotting the Big Dipper or Drinking Gourd constellation in the sky can help them find which direction is north without a compass. Remind the students that slaves used the Drinking Gourd constellation to help them find their way north to freedom. On the transparency, point to the two stars that make the side of the cup of the dipper. Show the students that by drawing an imaginary line through these two stars (called the Pointer stars) and continuing on, one comes to a very bright star called the North Star. Other stars may seem to move around in the sky, but the North Star always stays in the same place.
 

Open the specially-prepared umbrella and show the students the North Star inside the top of the umbrella. Show them that as you spin the umbrella, other stars and constellations such as the Big Dipper circle around the North Star. The North Star, however, stays in the same place. If one faces the North Star, one is facing north. To the right is east, to the left is west and behind is south. Tell them that for thousands of years, people in the Northern Hemisphere have looked for the Big Dipper constellation in the sky so they could find the North Star. Knowing which direction was north helped them find their ways across deserts, oceans or wilderness without getting lost.
 

Ask the students to watch the Big Dipper as you spin the umbrella. Point out that sometimes we see it with its cup up and sometimes with its cup down. Tell the students that if they could see stars in the daytime, they would see the Big Dipper spin around the North Star like this once every 24 hours. Ask: Are stars really moving in circles around the sky? (No. It is the Earth that is spinning, not the stars.)

Have two volunteers come to the front of the room. Designate one volunteer as the Sun and give him or her a flashlight. Tell the other volunteer that he or she is the Earth. Place a label that says Baltimore on the volunteer's shoulder and point out that this is where we live on the Earth. Have the Sun shine the flashlight on the Earth. Ask the Earth to spin slowly and to tell the class when Baltimore is having daytime and when Baltimore is having nighttime. Point out that the Earth is actually spinning at 800 mph. Each rotation of the Earth takes 24 hours or one day. Write 1 rotation'1 day on the board. As the Earth volunteer rotates, ask: If one rotation is one day, how many times will the Earth spin or rotate in one year? (365 times) Point out to the students that while the Earth is rotating, it is also moving in a circle around the Sun. It moves at 67,000 mph. Have the Earth volunteer rotate as well as move around the Sun in an orbit. Point out that it takes 365 rotations or days for the Earth to make one full circle around the Sun. This circle is called an orbit. Write 1 orbit'365 rotations or 1 year. Have the volunteers return to their seats.
 

Show the students the globe. Spin the globe on its axis and ask: Is this globe rotating or orbiting? (rotating) Swing the string with tape roll in an arc above your head. Ask: Is the tape roll rotating or orbiting me? (orbiting) Point out that as the Earth rotates, it remains the same distance from the Sun as it orbits it during the year. Remind the students that they learned about seasons in second grade. Ask: Why do we have seasons? Why does our climate change during summer, fall, winter and spring? (because the Earth is tilted) Remind them that during part of its orbit, the top half of the Earth where we live is tilted toward the Sun. The Sun's rays hit more directly on our part of the Earth. This is when we have summer. During the other part of the orbit, the top half of the Earth is tilted away from the Sun. The Sun's rays hit the bottom half of the Earth more directly. People who live there enjoy summer and we have winter.
 

Remind the students that we may learn about how the Earth rotates and how it orbits the Sun, but here on Earth it does not feel as if we are moving at all. When we look at the sky, it appears that we are standing still as the sun, moon, stars and planets move around us. Tell the students that next lesson they will see some illustrations of what people of long ago thought the universe must look like.

Possible Field Trips
Presentations at the Davis Planetarium at the Maryland Science Center simulate the night sky without the interference of lights, pollution, trees, buildings and clouds. The planetarium focuses on different themes but has presented shows on the Drinking Gourd and other constellations.
 

The Hubble Space Telescope Science Institute is in Baltimore on the Homewood campus of Johns Hopkins University. Call about programs and tours of their facilities. Their number is (410) 338-4700.

Third Grade - Science - Lesson 38 - Astronomy

Objectives
Describe why it appears as if the stars are circling in the sky.
Describe why astronomers build telescopes on mountain tops.
Create a list of facts about the Sun.

Materials
Pictures of geocentric and heliocentric universe models for transparency (attached)
A piece of waxed paper and a piece of clear plastic wrap
Pictures of the Space Shuttle and Hubble Space Telescope from Suggested Books
Pictures of galaxies from Suggested Books.

Suggested Books
Bailey, Donna. Far Out in Space. Austin, TX: Steck-Vaughn, 1991. Page 36 and 37 include photographs of the Space Shuttle and Hubble Space Telescope. Pages 22 and 23 contain illustrations of various types of galaxies.
Branley, Franklyn. Floating in Space. New York: HarperCollins, 1998. Another in the Let's- Read-and-Find-Out Science series, this book focuses on a space shuttle mission, the in- space life of astronauts and the work of the shuttle crew on the Hubble Space Telescope. Branley is the chairman of the American Museum-Hayden Planetarium.
Dailey, Robert. The Sun. New York: Franklin Watts, 1994. Pages 19 through 21 deal with Copernicus and Galileo and include an illustration of Copernicus. Page 30 contains a picture of the Sun's surface.
Kerrod, Robin. The Children's Space Atlas. Brookfield, CT: Millbrook Press, 1992. Page 83 includes a large illustration of Hubble.
Lambert, David. Stars and Planets. Austin, TX: Steck-Vaughn, 1994. Pages 6, 10 and 11 contain illustrations of the Space Shuttle which show how it is launched with rocket boosters. Pages 26 and 27 show different types of galaxies.
Lippincott, Kristen. Astronomy. New York: Dorling Kindersley, 1994. This Eyewitness Science series book contains many photographs and illustrations of telescopes. Pages 8 through 19 highlight ancient astronomy and the contributions of Copernicus and Galileo. Page 35 shows the Space Shuttle with its solid fuel rocket boosters.
Reid, Struan and Patricia Fara. Scientists. New York: Scholastic, 1992. Page 14 contains a short piece on Copernicus.
Simon, Seymour. Galaxies. New York: Morrow, 1988.
________. The Solar System. New York: Morrow, 1992. This is an extremely well-written tour of our solar system and includes an illustration on page 4 showing Earth's location in the Milky Way.
Stacy, Tom. Sun, Stars and Planets. New York: Random House, 1990. Pages 18 and 19 include illustrations of the Milky Way and other types of galaxies.
Stannard, Russell. Our Universe: A Guide to What's Out There. New York: Kingfisher, 1995. Pages 53 through 57 include illustrations of differently-shaped galaxies including the Milky Way.

Procedure
Remind the students that last lesson they learned about constellations. Ask: What constellation helps us find the North Star? (the Big Dipper or Drinking Gourd) Why would we want to locate the North Star? (It helps us find which way is north.) Does the North Star seem to circle the night sky the way the other stars do? (No, it stays still.) Are the stars really moving, circling the sky? (no) Why do they seem to move? (The Earth is rotating so it looks like the sky is moving.)
Tell the students that long ago people believed that the Earth stood still and the sun, moon, stars and planets circled around it. Show the students the transparency of the geocentric universe. Point out that the Earth is at the center of this model of the universe. Then in the 1500s, a man in Poland named Nicolaus Copernicus wrote a book that said the Sun, not the Earth, was the center of the universe. Copernicus said that it was Earth and the planets that moved around the Sun. Show the students Copernicus's picture of how he thought the universe looked. Tell the students that many people did not like Copernicus's new idea. They said it was a dangerous idea that went against what great thinkers had said. It even went against what was written in the Bible about the Earth's place in the universe. At first Copernicus decided not to publish his book with its new idea because he was afraid he would be punished by the Catholic Church. A few months before he died, Copernicus was finally persuaded to publish his book. The publishers wrote an introduction that said, "This is just a theory about the universe and could very well be wrong," because they, too, were afraid the Catholic Church would punish them.
Tell the students that a man named Galileo read about Copernicus's idea. The telescope had just been invented so Galileo decided to use the telescope to watch the planets. He wanted to look for evidence that might prove whether the Earth or the Sun was the center of the universe. He built his own telescope and with it spotted the moons of Jupiter. He measured the shadows on the Earth's moon. He watched the changes of sunlight reflected by Venus and decided that the Sun was the center of the universe just as Copernicus had written. In 1611 Galileo went to Rome to talk with Catholic Church leaders about how Earth and the planets orbited the Sun. When the Catholic Church leaders heard his evidence, they arrested him for spreading dangerous ideas. He was under house arrest until he died thirty years later.
Ask: How do astronomers today learn more about the Sun, planets and stars? (telescopes) Point out that telescopes today are much more powerful and much larger than the one Galileo built. Telescopes are often built on the tops of mountains. Ask: Why would astronomers want to build telescopes on the tops of mountains? (to be closer to the sky) Point out that dust, pollution, clouds and street lights of cities make it harder to see stars. Mountaintops are far away from city lights and often above the clouds. The air at the tops of mountains is cleaner, and thinner than down below. Show the students a piece of waxed paper and a piece of clear plastic wrap. Tell the students that looking through the Earth's atmosphere from a city is like looking through waxed paper. From a mountain top where the atmosphere is thinner and cleaner, it is more like looking through clear plastic wrap.
Tell the students that an even better way to get a clear picture of distant objects in space is to get out of the Earth's atmosphere altogether. Ask if any of the students have heard of the Hubble Space Telescope. If the students do not know anything about the Hubble, tell them that it is a powerful telescope sent up into space on the Space Shuttle. If available, show photos of the
Space Shuttle and Hubble Space Telescope from Suggested Books. Tell the students that now the Hubble Space Telescope maintains an orbit outside the Earth's atmosphere and sends computer pictures of space back to astronomers on Earth. Using it, astronomers can see 100 times more clearly than they can with any telescope on Earth. Point out that the Hubble Space Telescope Institute where the astronomers work is right here in Baltimore.
Show the students pictures of galaxies from Suggested Books. Tell them that Hubble has sent back pictures of huge clouds of stars we call galaxies. Write this word on the board. Tell the students that galaxies whirl like pinwheels in space. Some of these galaxies look like spirals or whirlpools. Some look like glowing blobs. Others look like spinning footballs. The galaxy where we live is a spiral galaxy called the Milky Way. Astronomers think the Milky Way contains 100 billion stars. Write Milky Way has 100,000,000,000 stars on the board. Among those 100 billion stars is our star--the Sun. It is two thirds of the way out from the center on one of its spiraling arms. Point out that the Sun is not the center of the universe the way Copernicus and Galileo thought. It is just a medium-sized star in a medium-sized galaxy in a universe full of stars and galaxies. But the Sun is our star and we couldn't live without it.
Tell the students to get out paper and pencils. Tell them that at the end of the lesson you will divide them into teams to play a game called Sun Facts. The team that is able to recall the most facts about our star, the Sun, will be the winner. Ask the students to listen carefully and take notes for their team's fact list. Ask: What do we get from the Sun? (light, heat, energy that makes the plants grow, weather) Ask: What do you think the Earth would be like if there was no Sun? (very cold, dark, lifeless) What do you think the Sun is made of? (Accept all answers.) Tell the students that the Sun, like the other stars, is a ball of flaming hot gas. It is much, much bigger than the Earth. More than one million Earths would fit inside the Sun. Ask: How far away from Earth do you think the Sun is? (Accept all answers.) Tell the students that the Sun is 93 million miles from Earth. If you were able to take a jet to the Sun, it would take 20 years to get there. Light travels much faster than a jet. Light from the Sun reaches the Earth in less than 8 2 minutes. The temperature on the surface of the Sun is 10,000 degrees Fahrenheit. The Sun burns nuclear fuel. It has been burning fuel for more than 4 2 billion years.
Divide the class into groups of five students. Ask each group to compile a list of Sun Facts that they recall from the discussion. Encourage the groups to use books in the classroom to find additional facts about our star, the Sun. Have the winning group read their Sun Facts to the class.

Third Grade - Science - Lesson 39 - Astronomy
Relative size and distance demonstration adapted from Planets, Moons and Meteors by John Gustafson.

Objectives
Compare relative sizes of the planets and their distances from the Sun.
Compile information from research and complete a planet chart.

Materials
Diagrams of the solar system from Suggested Books
A basketball, a quarter, a nickel, two unpopped kernels of popcorn, two grape or tomato seeds, two poppy seeds, a grain of salt
A Planet Collection (books on planets from Suggested Books)
Planet Chart (attached), colored pencils or crayons, paper for each of nine groups

Suggested Books
Apfel, Necia H. Voyager to the Planets. New York: Clarion, 1991.
Asimov, Isaac. A Distant Giant: The Planet Neptune. Milwaukee: Gareth Stevens, 1996. All the books in Asimov's series on the planets are excellent and include good illustrations and computer photos.
________. Mercury: The Quick Planet. Milwaukee: Gareth Stevens, 1989.
Berger, Melvin. Discovering Mars: The Amazing Story of the Red Planet. New York: Scholastic, 1992. Includes wonderful photos of Mars taken by Hubble.
Branley, Franklyn. Planets in Our Solar System. New York: Harpercrest, 1988.
________. Venus: Magellan Explores Our Twin Planet. New York: HarperCollins, 1994. Compares Earth to our sister planet.
Cole, Joanna. The Magic School Bus: Lost in the Solar System. New York: Scholastic, 1990.
Gibbons, Gail. The Planets. New York: Holiday House, 1993. The inside front cover includes an excellent diagram of the solar system. Basic information for each planet is presented in easy-to-read text.
Gustafson, John. Planets, Moons and Meteors. New York: Julian Messner, 1992.
Lauber, Patricia. Journey to the Planets. New York: Crown, 1990. While the text is for older readers, the black and white close-up photos of the surfaces of planets are truly impressive.
Leedy, Loreen. Postcards from Pluto: A Tour of the Solar System. New York: Holiday House, 1993. Delightful postcard descriptions of visits to the planets.
Reid, Struan and Patricia Fara. Space Facts. New York: Scholastic, 1987. Includes cartoon illustrations and facts on the planets, asteroids and comets.
Reigot, Betty Polisar. A Book About Planets and Stars. New York: Scholastic, 1988. On page 26 is some information necessary to complete the Planet Chart for each planet.
Ride, Sally and Tam O'Shaughnessy. Voyager: An Adventure to the Edge of the Solar System. New York: Crown, 1992. Heavily illustrated with pictures of the outer planets and their moons sent back by the Voyager space probes. Sally Ride was a Space Shuttle astronaut.
Simon, Seymour. Destination: Jupiter. New York: Morrow, 1998.
________. The Solar System. New York: Morrow, 1992.
Stannard, Russell. Our Universe: A Guide to What's Out There. New York: Kingfisher, 1995.
Vogt, Gregory. Mercury. Brookfield, CT: Millbrook, 1994. Books in this series contain a Quick Facts section in the back.
________. Venus. Brookfield, CT: Millbrook, 1994.

Teacher Resource
The Planets. New York: Barrett Productions, 1993. This 51-minute video is narrated by Patrick Stewart of Star Trek. The sound track of this tour of the solar system is Holsts' The Planets. It includes images collected by NASA from Viking, Mariner, Pioneer, Galileo and Magellan space probes.

Teacher Note
Before the lesson, prepare a relative distance scale for the solar system. Draw a 9 2-foot line on the board. At one end draw a circle to represent the Sun. On the line, at one inch intervals from the Sun, make four small dots. Label them Mercury, Venus, Earth and Mars respectively. Measure 10 inches from the last dot, make another dot and label it Jupiter. Measure 13 inches from Jupiter, make another dot and label it Saturn. Measure 27 inches from Saturn, make another dot and label it Uranus (pronounced YOUR-uh-nus). Measure 33 inches from Uranus, make another dot and label it Neptune. Finally, measure 25 2 inches from Neptune, make a dot and label it Pluto.

Procedure
Write solar system on the board. Point out that solar means having to do with the Sun. When people talk about solar energy, they are talking about energy from the Sun. Tell the students that our solar system includes the Sun plus everything that circles around it. This includes Earth and the planets, the moons that orbit the planets, asteroids, meteors and comets. The Sun's gravity keeps all these "heavenly bodies" orbiting around it instead of flying off into space. Show the students diagrams of the solar system from Suggested Books. Ask: What is at the center of the solar system? (the Sun) Ask a volunteer to come up and count how many planets are in the diagram of the solar system. (nine) Have the volunteer read the names of the planets. (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto)
Ask: When you look on a map and find a scale of miles, what does the scale tell you? (how many inches equals how many miles on the map) Tell the students that you are going to show them scale models of the Sun and planets so they can compare their sizes. Show the students the basketball and ask them to imagine that this is the size of the Sun. Show them a poppy seed. You will need to circulate through the classroom so the students can see this tiny seed. Tell the students that compared to the basketball sun, Mercury is the size of a poppy seed. Point out on the solar system distance line on the board that Mercury is the closest planet to the Sun.
Show the students a grape or tomato seed and tell them that compared to basketball Sun, this is the size of Venus, our next door neighbor planet. Point out Venus on the distance line. Show the students the other grape or tomato seed and tell them that this represents the size of Earth. It is about the same size as Venus. Point out Earth's place on the distance line. Show the students the other poppyseed and tell them that this represents the size of Mars compared to the basketball Sun. Ask: Mars is close in size to what other planet? (Mercury) Point out Mars on the distance line. Tell the students that Mercury, Venus, Earth and Mars are the inner planets. Their orbits are the closest to the Sun. These are also called the Rocky Planets. Ask: Why do you think these are called the Rocky Planets? (because they are made of rock) Tell the students that between the orbits of Mars and Jupiter is an asteroid belt. Asteroids are large and small pieces of orbiting rock.
Show the students the quarter. Tell them that compared to the basketball Sun, this is the size of Jupiter. Make a side-by-side comparison with the basketball and point out that Jupiter is the largest planet in the solar system but is still much, much smaller than the Sun. Point out its position on the distance line. Show the students the nickel. Tell them that the nickel represents the size of Saturn compared to the basketball Sun. Point out Saturn's position on the distance line. Show the students an unpopped kernel of popcorn and tell them that this represents the size of Uranus compared to the basketball Sun. Point out Uranus on the distance chart. Ask the students to compare the distance between the Sun and Earth and Uranus and Saturn. Show the students the other unpopped popcorn kernel. Tell them that this represents the size of Neptune. Ask: What other planet resembles Neptune in size? (Uranus) Point out Neptune's position on the distance line. Ask: Recalling the Sun Facts, how many miles are between the Earth and the Sun? (93 million miles) Ask the students to compare the 93 million mile space on the distance line from Sun to Earth with the distance between the Sun and Neptune. Tell the students that Neptune is nearly three billion miles from the Sun. Jupiter, Saturn, Uranus and Neptune are called the Gas Giants. Ask: What do you think these planets are made of? (mostly gases)
Show the students a grain of salt. Tell them that this is the size of Pluto compared to the basketball sun. It is the smallest of the planets, smaller than the Earth's moon. Point to Pluto's position on the distance line. Ask: As you move away from the Sun, would you expect the planets to be warmer or colder? (colder) Point out that astronomers think Pluto may be an ice ball.
Divide the class into 9 groups and assign a planet to each group. Distribute a Planet Chart to each group. Have the students use books from the Planet Collection in the classroom to find out facts about their planet. Encourage them to look at photos or illustrations of the planets in books and have a group member create a picture of the planet. After using them in Lesson 40, compile the Planet Charts and pictures in a Book of the Planets or a Planets bulletin board.
 
 

Planet Chart
 

Planet's Name_________________________________________
 

1. Distance from the Sun_______________________________million miles
 

2. How long it takes to
rotate once (in Earth days or hours)____________________________________
 

3. How long it takes to
orbit the Sun once (in Earth days, months or years)________________________
 

4. Number of moons or satellites_________________________________________
 

5. Description of planet's atmosphere_____________________________________

_________________________________________________________________
 

6. Surface temperature_____________________degrees Fahrenheit
 

7. Describe in sentences any special features of this planet.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

Third Grade - Science - Lesson 40 - Astronomy
Pixels from Space activity adapted from Mailbox Magazine, January, 1997.

Objectives
Chart the orbit and rotation times for the nine planets.
Create, transmit and receive a picture using pixel locations.

Materials
Illustration for transparency of planetary orbit and rotation (attached)
Pictures of planets and moons sent back by unmanned spacecraft from Suggested Books
Pictures of Voyager from Suggested Books
Pixels from Space worksheet for each student (attached)
Three crayons or pencils of different colors for each pair of students
A book that can stand up and function as a screen between partners

Suggested Books
Apfel, Necia H. Voyager to the Planets. New York: Clarion, 1991. A picture of the Voyager spacecraft is on pages 10 and 11.
Lauber, Patricia. Journey to the Planets. New York: Crown, 1990.
Ride, Sally and Tam O'Shaughnessy. Voyager: An Adventure to the Edge of the Solar System. New York: Crown, 1992. Pages 6 and 7 show an illustration of Voyager.
Simon, Seymour. The Solar System. New York: Morrow, 1992.

Procedure
Show the students the transparency of planetary rotation and orbit. Remind the students that the planets orbit the sun and also rotate. Remind them that one rotation is equal to one day. Point out the arrow that shows rotation on the transparency. Ask: Are days on other planets the same length as they are on Earth? (no) Ask the group that made a Planet Chart for Mercury to report how long a day on Mercury is. (59 Earth days long) Point out that Mercury rotates much more slowly than Earth. The Sun would appear to move very, very slowly across Mercury's sky. Point out the planetary orbit path on the transparency. Ask the Mercury group how long it takes for Mercury to orbit the Sun. (88 Earth days) Ask the Earth group how long it takes for Earth to orbit the Sun. (365 days) Ask: Which planet do you think is orbiting faster? (Mercury) Ask: Which planet is closest to the Sun? (Mercury) Tell the students that the closer something is to the Sun, the stronger is the pull of the Sun's gravity. Write gravity on the board. Tell the students that gravity is a force that causes objects to attract each other. Gravity is what keeps the planets orbiting the Sun, what keeps the moons orbiting the planets and what keeps objects on Earth from floating away. Point out that Mercury moves very fast in its orbit. If it didn't, it would be pulled into the Sun. Moving fast balances out the pull of the Sun's gravity.
Using information from their Planet Charts, have the students help you make a chart on the board to show how many Earth days, months or years it takes for each planet to orbit the Sun and how many Earth hours or days it takes for each planet to rotate once. Have students compare the lengths of a Saturn year and a Pluto year with the length of an Earth year. Have groups report on surface temperatures, moons and special features of their planets.
Show the students pictures from Suggested Books of planets and their moons that were sent back to Earth by unmanned spacecraft. Tell them that these unmanned spacecraft carry
cameras, radio receivers and transmitters, temperature sensors and other equipment so they can send back information about the planets to astronomers on Earth. Show the students pictures of the Voyager spacecraft or Mariner or Galileo spacecrafts. Point out that recently a spacecraft landed on Mars, collected Martian rocks and took pictures of its landscape. Tell them that a space probe called Cassini has been sent on a four-year mission to explore Saturn. Cassini will take pictures and sample gas particles in its atmosphere. A miniprobe inside the Cassini will travel to Titan, one of Saturn's moons. Astronomers have questions about Saturn: What holds Saturn's rings in place? What chemicals are in its atmosphere? Where did all its moons come from? Cassini will use radar to peek through the thick atmosphere of Saturn and will take a half million photos.
Ask: How do you think the photos will be sent back to Earth? (radio signals) Tell the students that computers change the pictures into tiny squares. Each square is called a pixel. Write this word on the board. The transmitter onboard the spacecraft sends the pixel locations for each photo back to Earth as radio signals. Antennae here on Earth pick up the radio signals from the spacecraft. Computers translate the radio signals back into pixel locations so astronomers can see the pictures.
Distribute a Pixels from Space worksheet to each student. Tell them that in this game they will communicate a picture by telling a partner the exact locations and colors of pixels. Point out that there are letters on one side of the grid and numbers on the other. Each square in the grid is a pixel and has a specific location. Ask the students to locate pixel 5D on the worksheet. Ask them to locate pixel 3A. When the students have mastered finding pixel locations, pair the students. Tell them that one partner will be the transmitter and one the receiver of a picture as in the game Battleship. Directions for Pixels from Space are on the worksheet.
When the students are finished with the game, ask: Do you think there are other solar systems besides our own? Do you think there are other planets besides the nine you have been learning about? (Accept all answers.) Tell the students that astronomers have found evidence of other solar systems--planets that orbit around other stars. They think they have found evidence of at least seven planets. Two of the planets are Jupiter-sized and orbit a star that is only 47 trillion miles away from us. If there were life on those planets, do you think they could send us pictures with radio waves? (Accept all answers.)

Possible Homework
Ask: If a spacecraft were being sent to explore the planet you reported on, what would you like it to find out about the planet? Write three questions you would want answered. How might a space craft collect the information? What equipment would you want onboard?
Imagine you received a picture from a planet outside our solar system, one that orbits a different star. Imagine that it is a close-up picture of the surface of the planet. Draw the picture you imagine receiving.
 

Pixels from Space!

Directions for the transmitter:
1. Stand a book on the desk between you and your partner so he or
she cannot see your paper.
2. Using three different colors, color in squares or pixels to make a simple design on the grid. Use only one color in each square. Leave some of the pixels blank. Do not let your partner see your design.
3. Give your partner the three crayons or pencils.
4. As the receiver calls out pixel locations (1A, 1B, 1C, and so on for every pixel) tell your partner the color of that pixel or if it is not colored in.
5. When your partner has finished calling out all the pixels, compare your design with his or hers. Do your pictures match?

Directions for the receiver:
1. When the transmitter is ready, call out the locations of the pixels one at a time starting with 1A, 1B, 1C, and so on for every pixel. For each pixel your partner will tell you a color to make that pixel or to leave it blank. Fill in the pixels one at a time as directed.
2. When you have finished calling out all the pixels, compare
your design with the transmitter's design.
Do your pictures match?
 
 

10

 

 

 

 

 

 

 

 

 

 

9

 

 

 

 

 

 

 

 

 

 

8

 

 

 

 

 

 

 

 

 

 

7

 

 

 

 

 

 

 

 

 

 

6

 

 

 

 

 

 

 

 

 

 

5

 

 

 

 

 

 

 

 

 

 

4

 

 

 

 

 

 

 

 

 

 

3

 

 

 

 

 

 

 

 

 

 

2

 

 

 

 

 

 

 

 

 

 

1

 

 

 

 

 

 

 

 

 

 
 

 
 

A
 

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J

 

Third Grade - Science - Lesson 41 - Astronomy

Objectives
Measure and calculate body weights on the moon.
List conditions on the moon.
Design a moon station that would allow humans to colonize the moon.

Materials
Illustrations of phases of the moon for transparency (attached)
Bathroom scale
Photos of astronauts on the moon and the surface of the moon from Suggested Books

Suggested Books
Asimov, Isaac. Why Does the Moon Change Shape? Milwaukee: Gareth Stevens, 1991.
Contains simple text and an excellent illustration showing how the moon reflects sunlight and shows the Earth its different phases.
Branley, Franklyn. The Moon Seems to Change. New York: HarperTrophy, 1987.
Davis, Don and David Hughes. The Moon. New York: Facts on File, 1989. While the text is too advanced for young readers, this book contains stunning illustrations showing how asteroids bombarded the moon's surface to create a cratered moonscape.
Gibbons, Gail. The Moon Book. New York: Holiday House, 1997. Includes information on Apollo landing, the moon's orbit, eclipses and legends about the moon.
Gustafson, John. Planets, Moons and Meteors. New York: Julian Messner, 1992.
Lauber, Patricia. Journey to the Planets. New York: Crown, 1990. Pages 20 through 31 contain excellent black and white photos of the moon.
Simon, Seymour. The Moon. New York: Four Winds, 1984. Simon has written a beautiful and haunting text, "The astronauts discovered that the moon is a silent, strange place. The moon has no air. Air carries sound. With no air, the moon is completely silent."
Sullivan, George. The Day We Walked on the Moon. New York: Scholastic, 1990. Follows the history of space exploration and includes sections on the Apollo program as well as the Space Shuttle.

Procedure
Write the word satellite on the board. Tell the student that satellite comes from a Roman word that means attendant, someone who waits on an important person. Point out that in astronomy, a satellite is something that orbits something else. Ask: Have you ever seen or touched a satellite? (Accept all answers.) Point out that the Earth orbits the Sun. It is the Sun's satellite. Therefore, the students have all touched a satellite--the Earth. Tell the students that the Earth has a natural satellite that human beings have been looking at for several million years. Ask: What is the name of the Earth's natural satellite? (the moon) Ask: When we look up at the sky at night and see the moon shining, is it making its own light? (no) Tell the students that the moon reflects the light of the Sun. The light we see here on Earth is coming from the Sun and bouncing off the moon.
Show students the transparency of the phases of the moon. Tell them that the moon appears to change its shape night after night. Sometimes it looks like a round disk, sometimes like a crescent and other nights like a circle cut in half. Tell them that the moon appears to change its shape because, as it orbits the Earth, sunlight bounces off it from different angles. Point out the new moon phase on the transparency. Tell the students that when the moon is dark with only a tiny light around its edges, it is called a new moon. Point out the illustration of the position of the moon, Sun and Earth when the moon is new. Tell them that when the moon is new, it is between the Sun and the Earth. We cannot see the light bouncing off its back side, only the little bit of light that wraps around its edges. Show the students the first quarter phase. Tell the students that when the moon is one-quarter of the way through its orbit around the Earth, the moon looks like this. Sunlight is hitting it from the side. Point out the full moon. Tell the students that when the moon is full, sunlight is striking it directly. We are seeing its entire lit side. Point out the moon's third quarter. Tell the students that now sunlight is hitting the moon from the other side. Once again we are seeing a half of its lit side. Tell the students that the moon takes 29 days to go through all its phases. When the moon is becoming more visible, people say the moon is waxing. When it is becoming less visible, people say it is waning. Point out that we measure time in days and years due to the Earth's rotation and orbit. Tell them that we measure time in months due to the moon's orbit.
Ask: What keeps the moon orbiting around the Earth instead of floating away in space? (Earth's gravity) Point out that just as the string held the tape roll, so the Earth's gravity holds onto the moon. Ask: Do you think the moon has any gravity of its own? (yes) Tell the students that the moon has one-sixth the gravity of Earth. Tell them that if they walked on the moon, they would weigh one-sixth of what they weigh here on Earth. Have several volunteers come forward, weigh themselves on the bathroom scale and record their Earth weights on the board. Ask the volunteers to divide their weights by 6 to find how much they would weigh on the moon. Tell the students that it is the moon's gravity pulling on the Earth's oceans that causes high and low tides.
Ask: Has a person ever walked on the moon? (yes) Tell the students that an American astronaut named Neil Armstrong was part of the Apollo 11 mission to the moon. Armstrong first set foot on the moon on July 20, 1969. As he stepped out on the moon's surface he said, "That's one small step for man, one giant leap for mankind." Ask: What do you think he meant when he said that? (Accept all answers.) Show the students photos of the astronauts on the moon and photos of the surface of the moon from Suggested Books. Tell them that the moon has no atmosphere--no air, no water, no clouds and no rain. Nothing grows on the moon. It is just rocks and moon dust. Remind the students that because there is no air on the moon, sound cannot travel. The moon is silent. On the lighted side of the moon the temperature is hot enough to boil water. On the dark side, the temperature is hundreds of degrees below zero. Ask: Looking at the photographs, what do you notice about the surface of the moon. (It is full of dents or holes.) Tell the students that these holes are called craters. Astronomers believe that they were caused by huge rocks from space called asteroids. Write this word on the board. Tell them that over billions of years many asteroids hit the surface of the moon. They pulverized the rock to dust and made deep holes the size of cities. Point out that some nights when they look at the moon they can see the darks and lights of its mountains and craters.
Ask the students to help you make a list on the board of conditions on our satellite, the moon (mountains and craters, very hot and very cold temperatures, no sound, no air, no water, no plants, no changing weather, 1/6 Earth's gravity) Ask the students to imagine that they are being sent by spacecraft to colonize the moon. Keeping in mind what humans need in order to survive, what problems would they as pioneers have to solve? Ask the students either individually or in groups to design a moon station that would enable them to live on the moon.
 

Bibliography

Apfel, Necia H. Voyager to the Planets. New York: Clarion, 1991. (0-395-55209-5)
Asimov, Isaac. A Distant Giant: The Planet Neptune. Milwaukee: Gareth Stevens, 1996. (0-836-81231-X)
________. Mercury: The Quick Planet. Milwaukee: Gareth Stevens, 1989. (1-555-32360-X)
________. Why Does the Moon Change Shape? Milwaukee: Gareth Stevens, 1991. (0-836-80438-4)
Bailey, Donna. Far Out in Space. Austin, TX: Steck-Vaughn, 1991. (0-811-42525-8)
Barrett, N.S. Night Sky. New York: Franklin Watts, 1985. (0-531-10004-9)
Berger, Melvin. Discovering Mars: The Amazing Story of the Red Planet. New York: Scholastic, 1992. (0-590-45221-5)
Branley, Franklyn. The Big Dipper. New York: HarperCollins, 1991. (0-064-45100-3)
________. Floating in Space. New York: HarperCollins, 1998. (0-060-25432-7)
________. The Moon Seems to Change. New York: HarperTrophy, 1987. (0-064-45015-1)
________. Planets in Our Solar System. New York: Harpercrest, 1988. (0-690-04581-6)
________. The Sky is Full of Stars. New York: HarperCollins, 1981. (0-690-04119-5)
________. Venus: Magellan Explores Our Twin Planet. New York: HarperCollins, 1994. (0-060-20384-6)
Cole, Joanna. The Magic School Bus: Lost in the Solar System. New York: Scholastic, 1990. (0-590-41429-1)
Dailey, Robert. The Sun. New York: Franklin Watts, 1994. (0-531-20105-8)
Davis, Don and David Hughes. The Moon. New York: Facts on File, 1989. (0-816-02046-9)
Gibbons, Gail. The Moon Book. New York: Holiday House, 1997. (0-823-41297-0)
________. The Planets. New York: Holiday House, 1993. (0-823-41040-4)
Gustafson, John. Planets, Moons and Meteors. New York: Julian Messner, 1992. (0-671-72534-3)
Kerrod, Robin. The Children's Space Atlas. Brookfield, CT: Millbrook Press, (1-562-94164-X)
Krupp, E.C. The Big Dipper and You. New York: Morrow, 1989. (0-688-07192-9)
Lambert, David. Stars and Planets. Austin, TX: Steck-Vaughn, 1994. (0-811-49246-X)
Lauber, Patricia. Journey to the Planets. New York: Crown, 1990. (0-517-58125-6)
Leedy, Loreen. Postcards from Pluto: A Tour of the Solar System. New York: Holiday House, 1993. (0-823-41000-5)
Lippincott, Kristen. Astronomy. New York: Dorling Kindersley, 1994. (1-564-58680-4)
Reid, Struan. Space Facts. New York: Scholastic, 1987. (0-590-22512-X)
Reid, Struan and Patricia Fara. Scientists. New York: Scholastic, 1992. (0-590-62180-7)
Reigot, Betty Polisar. A Book About Planets and Stars. New York: Scholastic, 1988. (0-590-40593-4)
Rey, H.A. The Stars. Boston: Houghton Mifflin, 1952.
Ride, Sally and Tam O'Shaughnessy. Voyager: An Adventure to the Edge of the Solar System. New York: Crown, 1992. (0-517-58158-2)
Simon, Seymour. Destination: Jupiter. New York: Morrow, 1998. (0-688-15620-7)
________. Galaxies. New York: Morrow, 1988. (0-688-08064-5)
________. The Moon. New York: Four Winds, 1984. (0-590-07883-6)
________. The Solar System. New York: Morrow, 1992. (0-688-09993-9)
Stacy, Tom. Sun, Stars and Planets. New York: Random House, 1990. (0-679-80862-0)
Stannard, Russell. Our Universe: A Guide to What's Out There. New York: Kingfisher, 1995.(1-856-97551-7)
Stott, Carole. Night Sky. New York: Dorling Kindersley, 1993. (1-564-58393-7)
Sullivan, George. The Day We Walked on the Moon. New York: Scholastic, 1990. (0-590-45587-7)
Vogt, Gregory. Mercury. Brookfield, CT: Millbrook, 1994. (1-562-94390-1)
________. Venus. Brookfield, CT: Millbrook, 1994. (1-562-94391-X)

Teacher Resource
The Planets. (video) New York: Barrett Productions, 1993.