Name C 1 Workbook Our Solar System pg. 0
Can You Planet? (From Universe At Your Fingertips, Astronomical Society of the Pacific) Sort out the planets. Next to each planet s name, put yes if the statement is true (Jupiter is larger than Earth Yes) or no if it is not true (Earth has rings No). Use this information to place the planets on the Venn Diagram! (Use the Planetary Fact Sheet on page 5.) Planetary Facts Helping Table Earth Jupiter Mars Mercury Neptune Saturn Uranus Venus Larger than Earth Has Ring(s) Has Moon(s) pg. 1
Use the information from the chart to place the planets in the correct circle or intersection of circles. Has moon(s) Has rings & moons Has rings pg. 2
Use the information from the chart to place the planets in the correct circle or intersection of circles! Larger than Earth Has moon(s) & larger than Earth Has rings & larger than Earth Has moon(s), rings & larger than Earth Has moon(s) Has moon(s) & rings Has rings pg. 3
Use the Venn Diagram, chart, and fact sheet to answer the following questions. 1. Which planets are larger than Earth? 2. Which two sets of planets are closest in size? 3. What percent of the planets are smaller than Earth? % (# of smaller planets divided by eight) 4. Which planets have moons? 5. Which planet has the most moons? 6. What is the total number of known moons in our Solar System? 7. What is the average number of moons per planet? (total number of moons divided by 8) 8. Which planets fit into all three categories? 9. Which planets have days that are longer than 24 hours? pg. 4
Planetary Fact Sheet Diameter Length of Day Moons Rings Earth 12,800 km 23 hrs 56 min 1 No Jupiter 143,000km 9 hrs 55 min 63 Yes Mars 6,800 km 24 hrs 7 min 2 No Mercury 4,900 km 59 days 0 No Neptune 49,500 km 16 hrs 7 min 13 Yes Saturn 120,600 km 10 hrs 39 min 62 Yes Uranus 51,100 km 17 hrs 14 min 27 Yes Venus 12,100 km 243 days 0 No pg. 5
Comparison of Rocky Planets and Gas Giants (modified from a graphic organizer found at Amazing Space) Using the Solar System Fact Sheet, compare and contrast rocky planets and the gas giants. Rocky Planets Composition (of what are the rocky planets made) Gas Giants Composition (of what are gas giants made) List the rocky planets a. c. b. d. List the gas giants a. c. b. d. Can a spacecraft land on the rocky planets? Can a spacecraft land on the gas giants? Type of atmosphere (thick, thin, thick to very thick, etc.) Type of atmosphere (thick, thin, thick to very thick, etc.) Where found in Solar System (near to Sun or far away) Where found in Solar System (near to Sun, or far away) Temperature range of planets (lowest to highest) Temperatures of range planets (lowest to highest) Are the rocky planets larger or smaller compared to gas giants? Are the gas giants larger or smaller compared to rocky planets? pg. 6
Number of moons (many or from few to none) Number of moons (many or from few to none) Solar System Books Assignment Read three books about the Solar System. After you have completed the books, complete the worksheet. Title of Book Interesting Facts 1. 5. 2. 6. 3. 7. 4. 8. Title of Book Interesting Facts 1. 5. 2. 6. 3. 7. 4. 8. pg. 7
Title of Book Interesting Facts 1. 5. 2. 6. 3. 7. 4. 8. Planet Books Assignment Read two books about the planets. After you have completed the books, complete the worksheet. Title of Book Interesting Facts 1. 5. 2. 6. 3. 7. 4. 8. pg. 8
Title of Book Interesting Facts 1. 5. 2. 6. 3. 7. 4. 8. Strange Neptune Emily Sohn From Science News for Kids Jan. 17, 2007 Astronomers look for rules. They seek theories and develop models that tidily explain how planets form, how moons move, and how the universe came to look the way it does. But these scientists also keep finding exceptions to their rules. In our planetary neighborhood, Neptune is one of the more delinquent objects. This image of Neptune was captured by the Voyager 2 spacecraft in 1989. NASA pg. 9
The eighth planet in our solar system is about 2.7 billion miles from the sun and very cold. Yet some mysterious source of energy powers winds that gust up to 1,000 miles per hour. Neptune's moon Triton, which spouts geysers of ice, orbits the planet at a weird angle. And unlike the gas giants Saturn and Jupiter, Neptune and its neighbor Uranus are heavy and made of ice and rock. These and other unusual features have puzzled scientists for decades. "Neptune is peculiar," says Craig Agnor, a planetary scientist at the University of California, Santa Cruz. Recent discoveries have added to the intrigue. "The outer solar system is where we're making discoveries right now that are changing our fundamental understanding of the solar system," Agnor says. Although there's nothing in the works yet, two teams of researchers recently developed proposals for a possible mission to Neptune. Crazy moons Our only close look at Neptune and Triton came in 1989, when the Voyager 2 spacecraft took pictures of both objects. In the meantime, astronomers have observed the blue planet with telescopes on Earth and in space. Triton is the largest of Neptune's 13 known moons, or satellites. Several of them were discovered in just the past few years. And these moons are particularly quirky, Agnor says. This artist's illustration shows three moons of Neptune discovered in 2002. David A. Aguilar, Harvard-Smithsonian Center for Astrophysics pg. 10
Most satellites fit into one of two categories. Satellites that orbit close to a planet, like Earth's moon, follow a roughly circular path around the planet's equator, moving in the same direction in which the planet spins. More distant satellites tend to have strange, tilted orbits. Compared with the spin of their planets, they sometimes orbit in the opposite direction. Many of Neptune's moons, including Triton, break these rules. Triton has a tilted orbit and travels in a direction opposite to Neptune's spin, even though it's fairly close to the planet. It's possible, Agnor suggests, that Triton used to be part of the Kuiper belt, a wide band of icy bodies beyond Neptune's orbit. What's more, Triton might once have had a satellite of its own. Agnor's theory builds on recent studies showing that about 10 percent of Kuiper belt bodies, including Pluto, have satellites. When Triton and its buddy passed by Neptune, the planet's gravity could have pulled them apart, slowing Triton down and capturing it as a moon. Craig Agnor created this image to show Triton and its companion approaching Neptune. This encounter led to the capture of Triton, which entered an unusual orbit around Neptune. Craig Agnor, University of California, Santa Cruz If true, Agnor's model gives insight into the early days of our solar system, says Dave Atkinson of the University of Idaho in Moscow. Atkinson was a member of one of the Neptune mission proposal teams. pg. 11
Mission to Neptune Sending a mission to uncover Neptune's secrets would be useful, Atkinson says, but it's easier said than done. Neptune is so far away that it would take between 6 and 14 years to get there, he says, depending on the technology used. Once there, a spacecraft would face frigid temperatures and powerful windstorms. Some scientists speculate that there's liquid water deep inside Neptune's core, but no technology exists that would allow a probe to survive the high pressures inside the planet's depths. It would also be impossible to send signals back to Earth from such an environment. Neptune's Great Dark Spot is a giant storm in the planet's atmosphere. NASA Ideally, a Neptune mission would also carry a lander to investigate Triton's icy geysers. The problem with this plan is that the moon's atmosphere is too thin to support a parachute like the ones that have delivered landers to the surface of Mars. Instead, a Triton lander would have to use rockets to slow itself down. This would require extra fuel and equipment, which are both heavy and expensive to transport. "Given the cost and complexity... of getting a lander to the surface of Triton, is it worth it for the amount of science we would get back?" Atkinson wonders. "That's the question I don't know if we can answer." Moving outward Whether a probe lands on Triton or a spacecraft simply flies by, visiting Neptune would give scientists insight into more than just our own planetary neighborhood. Scientists continue to discover Neptune like planets around other stars. And understanding how pg. 12
our own solar system fits together is the first step toward understanding how others work. This illustration, which shows what the view from Triton toward Neptune might be like, also gives an idea of how much Triton's orbit is tilted. NASA "We study giant planets to look inside at ourselves and to look far away," Atkinson says. "They're a connecting point between us and the universe out there." In a move toward exploration of the outer planets, scientists are working on building lighter, smaller probes. They're also developing new technologies that could operate in extreme environments. The earliest a spacecraft could arrive at Neptune would be 2033, and getting there that soon is unlikely. By then, many of the scientists working on the project now will be long retired, and you could be taking their place. Researchers such as Atkinson hope you will. "I still feel like a kid when I do this stuff because it's so cool," Atkinson says. "We're like kids on Christmas Day. People get so excited, even when [a Neptune mission] might be... years away." Questions 1. Why does the author of this article describe Neptune as a "delinquent object"? pg. 13
2. What makes landing on Triton so difficult? 3. When Dr. Dave Atkinson says "We study giant planets to look inside at ourselves and to look far away," what does he mean? 4. Would you be in favor of funding a mission to Neptune? Why or why not? 5. On average, Neptune is 4,500,000,000 kilometers from the sun. Venus is on average only 108,000,000 kilometers from the sun. On average, how many times farther is Neptune from the sun than Venus is? pg. 14
Comparison of Comets and Asteroids (modified from a graphic organizer found at Amazing Space) Using the Solar System Fact Sheet, compare and contrast comets and asteroids. Comets Asteroids Source: Astronomy Picture of the Day, December 28, 2005 (Source: Astronomy Picture of the Day, March 30, 2007) Composition (What it s made of) Composition (What it s made of) Where are they found in the Solar System? Where are they found in the Solar System? Can it be seen without a telescope? Can it be seen without a telescope? Average distance from Sun Average distance from Sun Estimated number Estimated number pg. 15
- Falling Stars The sight of a falling star is always exciting. Before the word look! is out of your mouth, the streak of light is gone. You point to where it was and ask others if they saw it, too. Often, no one else sees the speedy flight of light flash by, and you are left trying to describe what you saw and felt. You stare at the dark space, hoping another will streak across the sky. What is a falling star? A falling star is not a star at all. It is not even a piece of a star. Stars are huge balls of burning gas sending off great amounts of energy in the form of light and heat. Stars are much bigger than our planet. Stars do not fall; they stay in their own places in their own galaxies. Our sun is a star. A falling star is a meteor. Meteors are streaks of light in the sky that we can see when a small speck of dust burns up high in the air above us. Where do these specks of dust come from? Comets! Astronomers call these pieces of comet dust meteoroids. Meteoroids are usually smaller than a grain of sand. Some meteoroids are bigger, but most are tiny. Meteoroids hit the Earth s atmosphere at super-high speed, sometimes faster than 90,000 miles per hour. The friction between the tiny meteoroid and the atmosphere creates the light that we recognize as a meteor (or falling star ).The dust speck that burns up is called a meteoroid. The flash of light is called a meteor. Meteors usually last just a second or two. pg. 16
Sometimes, there are meteor showers. The heavens are a black theater for an amazing display of silent fireworks. It is exciting to watch all these meteors shoot through the dark sky. There are so many that if you watch with a friend, you will probably see some of the same and some different ones. Scientists also watch these meteors and record the numbers, the brightness, and the paths of these beautiful fireworks of nature. In a meteor shower, many shooting stars seem to fall from one area of the sky. Why do we have meteor showers? They happen when the Earth passes through the tail of a comet. Like the dust cloud surrounding Pigpen in the Peanuts comics, a meteoroid stream travels along with the comet on its orbit through the Solar System. Some people are confused by comets and meteors. A comet is different from a meteor. A comet is usually larger and travels slowly across the night sky. A very bright comet only appears once or twice in a century but it remains in the sky for many days or months. Comets appear to be bright balls with fat tails. They do not fall rapidly in the sky; you would have to watch one for hours or days to see its movement. The center of a comet is a ball of frozen gas, dust, and water. Like planets or moons, comets orbit around the Sun. The comet that causes the Leonids is called Tempel-Tuttle. It is named after two scientists who discovered it at the end of 1865.The scientists were not working together; one was in France and one was in America. They were each looking through telescopes. Both astronomers spotted the comet and reported their finding. The comet they found was not a big, bright comet. It is so small that it can only be seen with a telescope. The comet Tempel-Tuttle is about two-and-a-half miles in diameter. When comets get close to the Sun, they begin to warm up and their icy material begins to melt. Tiny grains of dirt that have been riding on the comet for perhaps four and a half billion years fly off into space to join a long stream of orbiting meteoroids. When the Earth hits this stream of comet junk from Tempel-Tuttle, meteors seem to shoot out of the constellation Leo. That s why this meteor shower is called the Leonids. The Leonids are famous. The reason that the Leonids are so famous is that sometimes they cause a meteor storm! In a meteor storm, over 1,000 meteors blaze across the sky every hour. In 1833, people all over America woke up to see hundreds of stars falling every minute! All night, the sky was brightened by meteors that rocketed through the night by the thousands! Since no telescopes or fancy equipment were needed to see the storm, ordinary people were able to see that wonderful and rare sight. Many artists tried to paint pictures of the rain of stars that fell so heavily that night. Newspapers pg. 17
ran many stories about the storm. What they saw was a Leonids meteor storm. This display was so beautiful and amazing that meteors suddenly captured the attention and imagination of people everywhere. Scientists were inspired to begin a serious study of meteors and their causes. The best way to watch a meteor storm is with your eyes. Telescopes are not required. Dress warmly. Set up a comfortable lounge chair with blankets and snacks or spread out a blanket. Lie down and look up at the sky. Watch the beautiful flashes of light from tiny sky candles created in the long-ago dawn of our Solar System. Directions Some of the following words and phrases describe comets. Some words and phrases describe meteors. Some words and phrases describe meteoroids. Some describe more than one. Based on what you learned in the article Falling Stars, write comets, meteors, and/or meteoroids by the appropriate words and phrases. Shooting stars Composed of minerals and ice Orbits Sun Has a tail Speedy streak of light Usually the size of a grain of sand Hits the atmosphere faster than 90,000 miles per hour Surface melts into gas and dust when gets close to Sun Visible for a second or two Travels slowly across the night sky May come in showers or storms Remains in the sky for many days or weeks pg. 18
Asteroid, Comet, and Meteor Books Assignment Read three books, one about asteroids, one about comets, and one about meteors. After you have completed the books, complete the worksheet. Title of Book (Asteroid Book) Interesting Facts 1. 5. 2. 6. 3. 7. 4. 8. Title of Book (Comet Book) Interesting Facts 1. 5. 2. 6. 3. 7. 4. 8. Title of Book (Meteor Book) pg. 19
Interesting Facts 1. 5. 2. 6. 3. 7. 4. 8. What Comets Are Made Of Emily Sohn Science News for Kids July 25, 2007 Astronomers are watching a comet break into pieces, practically before their eyes. Their observations, reported by scientists at Johns Hopkins University's Applied Physics Laboratory in Laurel, Md., are giving surprising insight into the structure of these space objects. Comets are fairly small (about 12 miles across or less) balls of ice, rock, and dust that make long, noncircular orbits around the Sun. When a comet gets near the Sun, the star's heat melts some of it, creating what looks like a tail. At this stage, it looks somewhat like a tadpole. When the comet 73P/Schwassmann-Wachmann 3 broke apart in June 2006, it produced at least 68 chunks, including this large piece, called Fragment B. H. Weaver/JHUAPL, M. Mutchler and Z. Levay/STScI, NASA, ESA pg. 20
Comets sometimes burst into pieces when the Sun's heat turns their ice into water vapor. By studying these chunks, astronomers can compare the material at the center of a comet with material at its surface. The scientists expected that a comet's center would look different from its surface. That's because comets probably formed at the same time as the solar system, so the material at the center has probably remained unchanged for just as long. The surface material, on the other hand, is changed by the Sun's radiation. For the new study, the Johns Hopkins team observed the breakup of a comet called 73P/Schwassmann-Wachmann 3 (SW3). The comet orbits the Sun every 5.34 years. In 1995, SW3 split into at least five chunks. In June 2006, it passed within a relatively close 11.7 million kilometers (7.3 million miles) of Earth. Around that time, it disintegrated even more. Scientists counted 68 fragments. The two largest chunks are called B and C. Each is several hundred meters wide. The scientists studied both chunks using NASA's Infrared Telescope Facility and the Keck II telescope, both on Hawaii's Mauna Kea. The researchers found that B and C have nearly identical compositions, with the same proportions of substances such as water and carbon dioxide. Those results suggest that comets have maintained more of their original form than scientists had expected. "We were really lucky" that the comet came close enough for astronomers to make observations soon after a breakup, says lead researcher Neil Dello Russo. Because this was the first study of its kind, the scientists don't yet know whether all comets are the same, inside and out. Emily Sohn Describe comets (of what are they made, size, etc.) pg. 21