Teacher Activity Guide: Scholastic's The Magic School Bus Explores The Solar System
Updated: April 14, 2004
Scholastic's The Magic School BusŪ Explores the Solar System takes you and the children in your class on an interactive tour of the planets and many of their moons in our solar system. The story begins in Ms. Frizzle's wacky classroom, the starting point for all of The Friz's adventurous field trips. The whole Magic School Bus gang piles into the bus for a trip to the planetarium. But, as any fan of the series can tell you, Ms. Frizzle's field trips are never ordinary. The bus turns into a rocket ship and blasts into space. A mysterious mishap makes the bus spin out of control-and Ms. Frizzle disappear.
Where is Ms. Frizzle? Lost on one of the planets or their moons, children will soon learn. To find The Friz, your students and The Magic School Bus gang must search the solar system for clues.
Along the way, they learn basic solar system facts, play space-age video games, and conduct science "experiments" on the screen. They even get to hop out of the bus to see planets and moons up close.
On This Page
Overview
Activities
The ten Science Adventures will help you and your students fully explore the CD-ROM program-and beyond. Each one includes hands-on science activities and discussion starters for use before and after viewing the program.
Think and Discuss
Many of the lessons begin with an intriguing science question to spark students' natural curiosity. Ask the question and let students brainstorm possible answers. Encourage students to explore solutions during their fun computer tour of the solar system.
Computer Buddies
Pairing up students at the computer will encourage them to discuss the fascinating situations they'll encounter on their space trip.
Hands-On Science
Each Science Adventure offers hands-on experiments and explorations to do before, while, and after you use the CD-ROM program. Students can work in groups or alone.
Computer Basics
Clickables
Many objects and people on the screen are clickables: Point the cursor at something and click the mouse to see what happens. If nothing happens, it's not a clickable.
Special Reports
Ms. Frizzle's classroom contains a series of reports on the planets. Click on a report on the wall to open it up. Then click on one of the three icons: "At-a-Glance," "Why I Want to Visit," or "Cool Facts. "(Students can access this same information in the bus.)
The Field Trip
Clicking on the bus, which is outside the classroom window, will start the field trip into space. DON'T click on the bus until you're ready to take the trip. If you accidentally do, click on the "door" to get back to the classroom.
On-Screen Help
Anytime you're not sure what to do, click on Liz the Lizard for help.
Special Reports II
After you blast off and The Friz gets lost in space, you are in control of the bus! Hanging from the ceiling is a monitor. Click on the red arrows to flip through the planets. Then click on the planet to access a report. They're the same reports that were in Ms. Frizzle's classroom.
Travel
Find the "Planet Picker" in the center of the dashboard (a diagram of the solar system right above the wheel). Click on it to see all nine planets and the Earth's moon on the viewing screen. Click on the planet or moon you would like to visit. Then click on "GO" to the left of the Planet Picker. You can visit the planets in any order, as many times as you like.
Explore the Surface
Once you land on a planet or moon, click on the "Door "to the right of the dashboard to explore the surface.
Characters Speak
The Magic School Bus characters will join you on the surface. Click on them to make them talk.
Wacky Objects
Click on objects on the moon or planet surface (rocks, for example) to see wacky things happen.
Games
Click on the round satellite-like icon in the upper corner to play a space-age video game.
Tokens
If you win a token playing a game, it is taken back to the bus for you automatically. When you click on a token in the bus, you can put it into the left-hand slot in the dash. When you do this you get a Friz clue and a chance to find her using The Friz Finder.
Science "Experiments"
On every planet or moon surface, Tim's sketch pad sits on the ground. Click on it to do an on-screen "experiment."
Leave a Planet
Click on The Magic School Bus to go back inside it. There, you can use the Planet Picker to choose a different planet to explore.
Leave a Planet
Click on The Magic School Bus to go back inside it. There, you can use the Planet Picker to choose a different planet to explore.
Finding the Friz
After you find The Friz (and win the game!) you are automatically taken back to Earth.
Our Solar System
Children may know their home address by heart: street, city, and state. But what's their celestial address? Where is our home planet in relation to the rest of the universe? The "street" address is the third planet from the sun. The "city" address is the solar system. And the "state" address is the Milky Way galaxy, of which our solar system forms one very small part.
Science Concepts
| • | The solar system consists of the sun and all the objects orbiting it, including nine planets, dozens of moons, millions of asteroids, and billions of comets. |
| • | It may seem like the planets in our solar system are in the same neighborhood, but even "close" distances in space are very, very great. |
Background
The word "solar" means sun. So a solar system is a sun, plus everything within its powerful gravitational reach.
Important Tips
| • | The Planet Picker map on the CD-ROM shows all nine planets in order, from those closest to the sun to those farthest away. What it doesn't (and can't) show is scale. To gather data on the actual sizes of the planets, students can click on the planet reports on the wall of the classroom or on the monitor hanging from the ceiling in the bus. |
Activities
Intriguing Science Question: Are there other solar systems out there?
Answer: There are other solar systems out there. Every star is a sun and is also the center of a solar system. These solar systems probably contain undiscovered planets.
1. How Far is Far?
Ask children: If someone asked directions to the moon, how would students describe the distance to travel there from Earth?
The moon is far (252,000 miles at its farthest). But how far is far? Far compared to what? The moon is close compared to Pluto! Measuring relative distances in space is an important concrete step toward understanding why space travel is so difficult.
The Earth's equator is about 25,000 miles long; wrap a string around a globe and cut it. How many strings away is the moon? (Have advanced students do the math themselves; drop the thousands and round off figures: 250 divided by 25 equals 10.) Wrap a string around the Earth 10 times, cut it, and stretch it out. Place a small ball (i.e., the moon) this distance away from the globe. Use the string unit to compare this distance to "far-away "earthbound trips-California to New York, for example. Remind students that the moon is our nearest neighbor. The sun would be almost 4,000 strings away!
2. Meteorite Park
Ask children: What happens when meteors land on Earth? How do scientists know that they come from space?
Antarctica is like a meteorite park-one of the few places where fallen bits of our solar system are plentiful, out in the open, and well-preserved. Scientists look for elements (such as iridium) that are rare on Earth, but common in space. They also look for evidence of a big impact-a crater or melted bits of rock or glass (called tektites) that have re-solidified.
Have students investigate meteorites in science museums, planetariums, or reference books. What makes them different from Earth rocks? Do they all look the same? What kinds of shapes do they have? Colors? Textures?
Scientists discovered meteorites on Earth that resemble soil samples taken by the Viking Landers on Mars. How could Martian meteors get to Earth? Brainstorm theories based on what students know about Mars and space. One scenario suggests that a huge asteroid impact knocked pieces of Mars into space, and some reached Earth.
3. How Big is Big?
Ask children: If the sun were the size of a basketball (diameter: just under 10 inches), how big would Earth be?
Present concrete choices: the tip of a ballpoint pen, a peppercorn, a marble, an orange, a softball, a volleyball, and so on.
List all guesses on the board. Most will be way too large. The diameter of Earth is about one one-hundredth that of the sun- roughly one-tenth of an inch on this scale. Earth would be the size of a peppercorn. Mercury would be the size of the tip of a pen.
Earth and Its Moon
Earth - "The Blue Planet" - is like a desert oasis: teeming with life and lushness but surrounded by vast emptiness. It is the only known planet with just the right atmosphere, temperature, and natural resources to support plants and animals. The Earth's one and only moon couldn't be more different.
Science Concepts
| • | The moon is the closest body to Earth and so appears bright in the night sky. |
| • | Because the moon is so close, it's the only place in space (other than Earth) that humans have visited. |
| • | The moon doesn't have an atmosphere, wind, or rain, and so there's almost no erosion. |
Background
The Magic School Bus adventure begins at home-on a familiar planet, in a familiar-looking town, with familiar-looking friends. But just one tiny space step away-on the moon -everything changes.
The moon is smaller than Earth, and so its gravity is weaker (about one-sixth that of Earth). When students see the report on the moon, they see and hear films of Apollo astronauts hopping and jumping with ease in the weaker gravity. Because the gravity is weaker, the moon can't "hold onto" gases. No gas means no atmosphere. And no atmosphere means no weather -and very little or no erosion.
Important Tips
| • | The moon crater experiment asks students to change the angle and speed of a meteor and observe what kind of crater it makes on the moon. To start this experiment, click on Tim's sketch pad on the surface of the moon. |
| • | To blast back into space, use the Planet Picker to choose a destination other than Earth and then click on "GO." |
Activities
Intriguing Science Question: Why does the moon have so many more craters than Earth?
Answer: Most meteors that enter the Earth's atmosphere burn up and never hit the surface. The moon doesn't have an atmosphere, so lots of meteors hit the surface and create craters.
1. Meteor Splaat!
Ask children: What can you tell about a meteor just by looking at the crater it makes?
Scientists can tell a meteor's size, speed, and angle of impact by measuring its crater.
Your students can, too. Fill a pan with a couple inches of flour ("moon dust"). Smooth the surface with a ruler and dust the top with paprika, pepper, or cinnamon (so craters show up better). Drop a BIG marble into one half and a little marble (from the same height and angle) into the other half. How does the size of the marble affect the crater? (Bigger marbles make bigger craters and may toss up more flour.)
Remove the marbles and smooth over the flour. Next, drop two identical marbles from different heights. The higher marble is moving faster when it hits the flour, and so makes a bigger crater. The bigger and faster a meteor is, the greater the impact.
2. Moon-Watchers
Ask children: Does the moon look the same all over?
Ask students to draw a picture of the moon. Some may draw a round, white ball or maybe a quarter moon. With closer observation, students can draw a more scientific picture.
On a clear evening, have students observe a half moon. (Sunlight hits the moon at an angle and features cast distinct shadows.)
Ask students to describe the moon's features: dark spots (called mares), streaks, big craters, little craters, etc. Then have them draw a second picture of the moon to compare with the first.
3. Footprints Forever
Ask children: Where on Earth would footprints be preserved for a long time?
While seeing the report on the moon, students learn that the astronaut footprints will last for billions of years. No wind, water, or volcano will disturb them.
Where on Earth are objects well-preserved? Wherever the forces of erosion are minimal. (Frozen, snowless areas of Antarctica preserves dead seals for tens of thousands of years; bogs mummify prehistoric animals; etc.)
To watch erosion in action, make footprints by placing a foot-long patty of Plasticine or clay on waxed paper. Put waxed paper over it. Step on the paper to make a footprint. Remove the top paper. Set one footprint in a protected area indoors (such as a closet) to serve as a control. Set others outside. Have students predict how long the footprints will last, observe changes over several weeks, and record their observations in a diary.
Mercury
Mercury runs hot and cold and cold and hot as the tiny planet speeds around the sun. Its surface looks a bit like a dimpled golf ball with its round, similar-sized craters, regularly spaced, more or less.
Science Concepts
| • | Mercury is very hot (on the side facing the sun) and very cold (on the side facing away from the sun). |
| • | It orbits the sun faster than any other planet. |
Background
Both Mercury and Venus are close to the sun. Yet Mercury is both hot and cold and Venus is just hot. The reason? Atmosphere. Unlike Venus, Mercury's gravity is too weak to pull in a heavy, heat-trapping atmosphere. So the sun's heat radiates back into space quickly, leaving the dark side of the planet cold. A thin atmosphere also means more asteroids strike the planet surface and form craters.
Important Tip
Tim's sketch pad science experiment pits Mercury against Earth in a race around the sun. This activity helps students visualize the relative speeds of the planets, and reinforces that a "year" is the time it takes for a planet to travel once around the sun.
Activities
1. The Speediest
Ask children: Why is Mercury the fastest planet in the solar system?
Like its mythological namesake, the planet Mercury is speedy (about 100,000 miles per hour; one revolution around the sun in just 88 days). The closer to the sun, the stronger the sun's gravity. Mercury, of course, is the closest planet to the sun. So the sun pulls on it harder. Just to stay in orbit, Mercury has to maintain a very high speed.
Demonstrate how this works by tying a metal washer to a two-foot string. Grab the other end and swing the string just fast enough to keep the weight circling. Repeat with a shorter string. You have to spin the shorter one faster to keep the weight "in orbit." Planets aren't attached to the sun with string, but the force of gravity is similar.
2. Running Hot and Cold
Ask children: Can an area be hot and cold at the same time? How?
Temperatures on Mercury range from 750 degrees Fahrenheit to colder than Pluto-well below the freezing point of water. How can one planet be so hot and so cold?
On a very sunny day, position thermometers outside: directly in the sun, partially in sun, in shadow, in indirect sunlight. Wait a few minutes and compare the differences in temperature. (You can do this in the classroom, using a strong desk lamp, but the temperature differences may not be as great.) The super-hot side of Mercury faces the sun directly for 176 days; the super-cold side is in total darkness during that time.
Venus
Venus is the closest planet to Earth, roughly the same size as Earth, and it has an atmosphere. But that's where the likenesses end. Sometimes called our "sister planet," Venus is more like a very distant cousin.
Science Concepts
| • | Venus is a good example of the greenhouse effect: clouds holding in the planet's heat. |
| • | The surface of Venus is very hot (about 800-900 degrees F.) all over. |
Background
Venus is shrouded in yellowish-white clouds of carbon dioxide, sulfuric acid, and other gases. Though Venus is closer to the sun than the Earth, that's not the main reason it's hotter. In fact, the clouds reflect more than 70 percent of the sun's radiation back into space. (That's why Venus is so bright in the sky.) The planet is hot because its clouds trap heat from the planet core.
Important Tips
| • | Tim's sketch-pad experiment on Venus shows how the temperature rises as clouds thicken over a planet-a model of the greenhouse effect. |
| • | While visiting Venus, point out to children that it's mostly flat with a few ridges and valleys. Data on surface features is largely courtesy of the spacecraft Magellan, which mapped Venus in 1990. |
Activities
1. Viewing Venus
Ask children: Why can we see Venus on some clear nights, but not on other clear nights?
Venus is closer to the sun than Earth. So sometimes it's on the opposite side of the sun-where we can't see it. Other times, it's right in front of the sun-and so gets washed out of view. Many times, however, Venus is very visible.
Magazines such as Sky and Telescope and Astronomy report when to look for Venus. If it appears just before sunrise, face due east and look about 45 degrees above the horizon. If it appears just after sunset, face due west and look 45 degrees above the horizon.
2. Melting Mountains
Ask children: Why is the surface of Venus much flatter than the surface of Earth?
The surface of Venus is hot enough to melt lead and make mercury boil. This extreme temperature softens the ground. On Venus, mountains are "relaxing," or smoothing out, into the soft crust. They sink into the crust before they can form high peaks. This process takes millions of years.
To demonstrate, set chocolate Kisses ("mountains") on top of three chocolate bars ("the crust"). Make three such models. Put one in a refrigerator, one at room temperature, and the third in a microwave oven for a few seconds (or in direct sunlight). Observe changes. Then heat the third model again. The base of the Kiss will liquefy and spread out; the still-solid portion will sink into the partially melted chocolate bar.
Mars
"The Red Planet" - Mars - has appeared in more science fiction movies and books than any other planet. While Venus is shrouded in mysterious clouds, the surface of Mars is much more visible. Its dusty, iron-coated land reflects a pale pinkish light all the way back to Earth. Look for it on the next clear evening.
Science Concepts
| • | Scientists have found no evidence of life on Mars. |
| • | Mars once had active volcanoes, lava flows, and rivers that contained water or possibly another liquid; now it doesn't. |
| • | Like Earth, Mars has seasons and polar ice caps because the planet is tilted on its axis. |
Background
Many spacecraft have visited Mars in the last two decades, including the two Viking Landers that touched down in the mid-1970s. The clear view of the surface and the intense scrutiny of scientists have made Mars the best-studied planet, second only to Earth.
The maps reveal a huge extinct volcano (Olympus Mons), the deepest canyon in the solar system, dried-up lava flows, and-possibly-riverbeds that are now bare. The polar ice caps, like those on Earth, grow and shrink with the seasons. Water can't exist in liquid form on Mars; it goes directly from ice to vapor (called sublimation).
Mars may once have been warmer, wetter, and more hospitable to life-perhaps hundreds of millions of years ago. Now it is basically a smaller, freeze-dried version of Earth.
Important Tip
| • | Tim's sketch pad science experiment on the surface of Mars challenges students to compare the surface features of Mars and Earth and decide which is which. While Earth has a thick atmosphere, a blue sky, many surface colors, and life, Mars does not. |
Activities
Intriguing Science Question: Does Mars have earthquakes, or should I say, "marsquakes"? How can we tell from Earth?
Answer: The Viking Landers measured two "Marsquakes," a big one and a small one. In addition, we can see cracks, or faults, on Mars. Quakes occur when pieces of a planet's crust collide along these faults.
1. Viewing Mars
Ask children: How could you tell Mars from a star in the sky?
Most of the planets are visible from Earth without a telescope (even Uranus appears faintly in a clear sky). Locating them and telling them apart from the stars is most of the fun. Once you find the planets, there's not much to see without a $1,000 telescope. For this reason, encourage students to take their stargazing and planet-watching casually. There are plenty of interesting things to see in the night sky; if they happen to spot a planet, they'll basically just need to know how to recognize it.
The word "planet" comes from the Greek word "wanderer." Planets don't appear to cross the sky in the same fixed pattern as stars; they "stray" on an irregular path. To see them " stray "takes several hours or even days of viewing. Fortunately, Mars is more distinct than other planets because it is pale pink, and not bright white. 2. The Mightiest Volcano
Ask children: Just how big is Olympus Mons, the biggest known volcano in the solar system?
Olympus Mons (about 15 miles high) is three times taller than Mount Everest (about 5 miles high); its crater alone could hold one of Earth's midsized volcanoes! To make a rough scale drawing, children will need half-inch graph paper. Draw a horizontal line at the bottom to stand for the base of the mountain. Then count 15 units high (one unit per mile) and make a mark. Have students draw and color the rest of the mountain between the line and the mark, based on photos of Olympus Mons.
To compare Olympus Mons to earthly objects, have students use the same technique to draw the Eiffel Tower (less than 1 unit high-about 1/4 inch), Mount Everest (5 units high), or other objects. Cut out these drawings and place them next to the drawing of Olympus Mons. Students may also want to draw in the height of a passenger jet (6 units high), a fighter jet (16 units high), and clouds (various heights).
2. All Cracked Up
Ask children: Why does Mars have so many lines, cracks, mountains, and canyons?
Bring several hard-boiled eggs into class. The eggs are much-simplified models of Mars (and the Earth, too). The shell is like the planet's crust, the white part is like the mantle (the molten rock below the crust), and the yolk is like the core. In the past, Mars had a liquid mantle and core that fueled its active volcanoes.
Gently crack the shell of the eggs into pieces; these are like tectonic plates, pieces of the crust. What happens when you push and pull on these plates? (They smash into each other.) Do students see "mountains" (pieces of shell rising above the egg)? How about fissures (cracks between the shells)? Point out that sometimes a shell slips underneath another shell. This happens along fault lines on Earth, too. Compare the cracked egg with a topographical map of Mars. What other similarities do students see?
Jupiter
Jupiter is by far the biggest planet and even has its own little "solar system" - a group of moons that orbit the planet in much the same way as the planets orbit the sun. Stunning photos from the voyager spacecrafts provide close-up views of Jupiter's colorful, fast-moving, and stormy clouds.
Science Concepts
| • | Jupiter is the biggest planet in the solar system. |
| • | It is one of the four "gas giants"(along with Saturn, Neptune, and Uranus). |
| • | The Great Red Spot is a giant hurricane that won't stop. |
Background
The gases of Jupiter's atmosphere zip around at incredible speeds. One "day" on Jupiter is less than 10 hours -amazingly short for a planet 10 times bigger in diameter than Earth. The speedy clouds are turbulent and stormy.
Jupiter and its four biggest moons (Io, Callisto, Europa, and Ganymede) are like a mini-solar system in at least four ways. The moons are planet-sized (Ganymede is bigger than Mercury!). They all orbit in the same direction. The denser ones are closer to the planet than the less-dense ones (just as the dense rocky planets are closer to the sun than the less-dense gas giants). And the spacing between moons isn't even; it gets greater as the moons get farther from Jupiter. Likewise, the planets get farther and farther apart from Mercury to Pluto.
Important Tip
Tim's sketch pad science experiment on Jupiter involves filling the planet Jupiter with other planets to measure its relative size. For example, 1,024 Earths would fit into Jupiter.
Activities
Intriguing Science Question: If Jupiter is farther from the sun than Mars, why is it hotter?
Answer: Jupiter's core, and not the distant sun, creates most of the heat on the planet. The fast-moving clouds hold in the heat and spread it evenly around.
1. By Jove, it's Jupiter!
Ask children: How and why do planets and moons get their names?
In general, people named celestial bodies for mythological figures. Jupiter is the biggest planet, and so bears the name of the most important god-the ruler of Mount Olympus. Have students research the myths behind other planets and moons and look for similar connections. For example, Mars is the god of war, named for its "bloody" red color. Pluto, the god of the underworld, is the name of the coldest and darkest planet. Not all of the names have obvious connections.
2. Swirling Red Hurricane
Ask children: How would you describe the movement of a hurricane? Fast? Slow? Moves in a circle? Moves in a line?
The Great Red Spot of Jupiter is a huge, spinning hurricane. It moves across the planet like a street cleaner: the stormy gases spin in fast circles while the whole hurricane moves forward. In general, all fluids (liquids and gases are considered "fluids") tend to move in circular patterns.
As a class, observe fluid patterns (how fluids-liquids and gases both-move). Fill a circular cake pan with an inch or so of water. Sprinkle cornstarch on the top to see better.
Next, run the tip of a spoon straight through the pan. Hurricane-like eddies will form to either side of the spoon. They spin in opposite directions-just as hurricanes above and below the equator do.
Next, start the water spinning by moving the spoon in a circle all around the edge. Look for more "hurricanes." Compare these patterns with pictures of Jupiter's Great Red Spot. Your "hurricanes" die out; scientists aren't sure why the Great Red Spot doesn't.
3. Moon Charts
Ask children: Why do some planets have more moons than others?
Have students investigate ideas by making moon charts. For example, maybe bigger planets have more moons because their greater gravity can pull in more objects. Then again, maybe not. To find out, chart planets by size and number of moons. (Access the planet reports on the wall of Ms. Frizzle's classroom.) Children will discover that, in general, big planets have lots of moons. But there are exceptions. Mars is half the size of Earth, and it has two moons. Venus is the same size, but has no moons.
So what's the answer? It depends on how you look at the data. Scientists often disagree about what data means, just as your students may disagree about what the moon data means. Also, the data is incomplete; scientists have discovered new moons around planets as recently as 1991. Other factors may contribute to the number of moons: the planet's location, whether it's rocky or gaseous, etc.
Saturn
In a lineup of planetary suspects, one planet is hard to miss: Saturn has the most spectacular rings of all. It is also the farthest planet ancient astronomers could see. A few centuries later, we now have close-ups: Saturn was a prime stop on the Voyager I and II tours of the outer planets in 1979-80.
Science Concepts
| • | Saturn has the most visible rings (Jupiter and Uranus have less distinct rings). |
| • | Largely made of gas, Saturn is less dense than water. |
Background
If you could put the planet Saturn in a giant tub of water, it would probably float. Like Jupiter, the planet is mostly made of lightweight gases. Also like Jupiter, Saturn has massive moons. The moon Titan is bigger than Mercury and has an atmosphere that's mostly nitrogen (as Earth does). Saturn's unique feature is a spectacular band of rings.
Important Tip
| • | Tim's sketch pad science experiment invites children to design their own ring system by mixing dust, ice, and rocks and spinning them into bands. |
Activities
1. Liquid Layers
Ask children: If Saturn is so huge and heavy, how could it float in a tub of water?
To experiment with density, layer several tall, straight-edged jars from bottom to top with at least two of the following liquids: Karo syrup, dishwashing liquid, salt water, ketchup, fresh water, and rubbing alcohol. (Color the salt water and fresh water with different food dyes to make them distinct.) The liquids will form layers, from the most dense to the least dense.
Have students experiment with floating objects in the jars (one per jar): a cork, a piece of chalk, a cherry tomato, a hard-boiled egg, a coin or marble. Why do these objects float at different points? Size doesn't matter, but density does. A big, heavy hard-boiled egg will float higher than a small, lighter marble. The reason: The egg is less dense (tightly packed) than the marble. Saturn weighs many, many tons, but it is less dense than water; its gases are spread out farther with lots of space in between.
2. Moon Grooves
Ask children: What happens when Saturn's moons zip through its rings?
Moons orbit within Saturn's rings and may affect how the gases, chunks of ice, and other debris form bands. To demonstrate, sprinkle sugar on a pie plate and spin the plate slowly with one hand. Hold a pair of tweezers on the plate as it spins-both points (moons) touching the plate. The tweezers push aside the sugar until it forms into distinct bands.
Uranus
Pronounced YER-a-nus, this blue planet is the third gas giant in a row. Voyager II zipped by the planet in 1986. The spacecraft revealed lots of tiny moons and 10 rings. But the surface of Uranus proved to have few exciting features - no big red spots, massive mountains, or huge impact craters. Its moon Miranda stole the show.
Science Concepts
| • | Uranus is unlike all the other planets in our solar system because it spins on its side. |
| • | Like Saturn and Jupiter, Uranus has a ring. |
Background
Uranus has 15 moons. One of these moons, Miranda, has a hodgepodge of rock formations that is unique in the solar system. Miranda looks like a patchwork quilt with crazy, crooked parts hastily sewn together. One theory is that the moon was literally blown apart by an asteroid, and then it reassembled any which way.
Uranus, by contrast, is a smooth, uniform blue ball of frozen gas (mostly methane). Because it's on its side, our view from Earth is either of the North Pole or the South Pole, not the equator.
Important Tip
Tim's sketch pad science experiment asks students to match the angle of rotation with the planet. They learn that Venus, Jupiter, and Mercury are straight up and down. Earth, Mars, Neptune, and Saturn rotate at a slight tilt. Pluto rotates at a greater tilt. And Uranus alone rotates almost completely on its side.
Activities
1. Color Me Blue
Ask children: Why is Uranus blue? Why do Jupiter and Saturn have lots of colors?
Gases, like liquids and solids, give off colors (they absorb and reflect different parts of the spectrum). Jupiter and Saturn consist of many different types of gases, and so they're more colorful. Uranus contains a lot of methane, which gives it the blue color.
To investigate colorful gases on Earth, have students use the school library or encyclopedias to research the "neon "lights of cities. They'll find that only the reddish-orange lights are neon; other color lights have other gases, such as argon.
2. Uranus? You'll Love It
Ask children: Why do we send spacecraft to study planets and moons?
Some people oppose space exploration as a waste of resources and money. How do your students feel? Have them research the pros and cons of exploring space. Have them design a travel brochure or poster that makes a case for visiting Uranus. Then discuss the reasons why some people oppose such visits.
Neptune
Neptune is a big, blue, slow-moving ball of frozen gas. It's so slow and so far-out, that it hasn't completed a full orbit around the sun since its discovery. One revolution takes 164 years, 280 days!
Science Concepts
| • | Astronomers predicted Neptune existed before they actually discovered the planet. |
| • | Neptune is mostly blue like Uranus (and also made largely of methane), but also has a dark storm similar to Jupiter's. |
| • | Triton is one of the biggest moons in the solar system and the only one with an atmosphere. |
Background
Plenty of people, probably even Galileo Galilei, spotted the planet Neptune as far back as the early 1600s. But they thought it was a star.
Astronomers finally caught onto Neptune thanks to some quirky movements of Uranus. They observed that some unidentified force was acting on Uranus. After careful measurements, they concluded that the force must be the gravity of a large planet, and they calculated just where that planet should be. In 1846, a German astronomer named Galle aimed his telescope at the precise spot inside the constellation Aquarius and found Neptune.
Important Tip
| • | On Neptune, Tim's sketch pad experiment lets students cut all the planets in half to see what's inside. |
Activities
1. Seeing the Unseen
Ask children: Why don't scientists know for sure what's on the surface of Neptune (or any other gas giant)?
The atmospheres of Neptune and the other three gas giants are so thick they mask everything below them. Have student teams use construction paper and other materials to create a model of a planet surface in a shoe box. The only restriction is that the surface can't rise above the rim of the shoe box. Tell students to tape waxed paper over the shoe box when they're done.
Have teams swap shoe boxes and study them without removing the waxed paper or touching the shoe box. Can they tell what's on the surface? How? Give them a flashlight. Now what do they see? How else could scientists find out what's inside the box? (Use sonar, or sound waves, to make a map; infer what's there based on the materials students had at their disposal; hold a magnet next to it, and so on.) To map Venus, spacecraft Magellan bounced radio signals off the surface.
Pluto
Don't believe everything you read about the planets - completely. Before 1930, school kids learned that the solar system had eight planets. Then an astronomer discovered Pluto. Pluto is the farthest and least-known planet - the only one that spacecraft have not visited.
Science Concepts
| • | Pluto is usually the farthest planet from the sun and is also the most unique. |
| • | We know very little about the planet and what we do know often changes when new evidence appears. |
Background
Even through powerful telescopes, Pluto looks dim and blurry. Imagine looking at a dull nickel that's 13 miles away. In 1978, astronomers discovered that Pluto has a large moon-Charon. Some scientists consider this moon a planet, making Pluto-Charon a double planet set. But keep in mind that almost everything we know about Pluto is subject to change.
Important Tip
On Pluto, click on Tim's sketch pad science experiment to discover that objects (including planets, spaceships, and satellites) must move at exactly the right speed to stay in orbit. If the object moves too fast, it soars into outer space. If it moves too slow, the planet's gravity pulls it down and makes it crash.
Activities
1. Hello, Pluto
Ask children: How would deep-space explorers talk to people back on Earth?
Radio signals can travel billions of miles, but not quickly. Signals from far-out space probes take days to reach Earth.
This delay makes communication tough. Try it! Split the class into four or six teams. Give each team building blocks or Legos. Half the teams (the builders) secretly make structures and record verbal instructions on a cassette tape.
Three days later, the other teams (the copiers) listen to the tape and try to build an identical structure. The copiers can record questions on the tape, but the builders must wait three days to listen and respond. Continue until the copiers make structures identical to the builders'.
2. Planet Hunt
Ask children: Why didn't scientists see Pluto until 1930?
Place a marble (Earth) on the 20-yard line of a football field. Put eight marbles (the other planets) at random spots across the field mounted on golf tees. Then challenge students to spot them from "Earth." If students do spot marbles, prompt them for details. It's tough!
