Name C 1 Workbook Our Solar System - Planets 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