Non-fiction: Way-Out World. What strange satellite circles the visible edge of the solar system?

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1 Non-fiction: Way-Out World Way-Out World By Hugh Westrup What strange satellite circles the visible edge of the solar system? The detonation of a single nuclear bomb can do catastrophic damage. So imagine the power of more than one bomb not just two or 10 or even 10 million, but 10 billion. Astronomers have evidence that a collision with enough force to equal the explosion of 10 billion nuclear bombs once happened in the solar system. Out of that crack-up was born one of the oddest things in space. Its name is Haumea. There is so much to learn about this newfound object, and we keep finding surprises, says Mike Brown, an astronomer at the California Institute of Technology. It s just crazy. ODD Balls The solar system is always changing. What astronomers know about it is changing even faster. Advances in telescope technology keep deepening their view of space, continually revealing new objects and new features on old objects. One example of that change in perspective is Pluto. For more than 70 years, astronomers considered it the ninth planet. Then, in 2007, the International Astronomical Union reclassified it as a dwarf planet. Like a planet, a dwarf planet orbits the sun. It also has enough mass, and therefore enough gravity, to give it a rounded shape. But it lacks pull; its gravity isn t strong enough to clear its neighborhood of most smaller objects the way that planets do. A year later Pluto was reclassified again. Now it s a plutoid. A plutoid is simply a dwarf planet that exists beyond Neptune, the eighth planet. As of 2011, four known dwarf planets are plutoids. Pluto, Eris, and Makemake are three. The fourth, discovered by Brown shortly after Christmas 2004, was originally called Santa. That name seemed less appropriate, however, the more that scientists learned about it. Haumea was a better fit. Haumea is the mother goddess of Hawaii, whose many children Article: Copyright 2010 Weekly Reader Corporation. All rights reserved. Weekly Reader is a registered trademark of Weekly Reader Corporation. Used by permission. 1

2 Non-fiction: Way-Out World sprang from various parts of her body. The plutoid Haumea is trailed by a swarm of small, icy bodies that once were part of it. Haumea also has a distinctive spin and shape. It rotates once every four hours six times faster than Earth does. That s the fastest spin rate of any major object in the solar system. When an object in space rotates that rapidly, it stretches the way pizza dough does when it s tossed and twirled in the air, says Brown. Haumea s quick spin has given it an oblong shape that looks like a squashed football, he adds. The same effect is at work on Earth. But because Earth turns less quickly, it bulges only slightly at its equator. In addition to the icy debris that trails Haumea, a pair of icy moons orbit it. Called Hi iaka and Namaka, the moons were named after two of the goddess Haumea s mythical daughters. Blast Off A fast rotation, a squashed shape, two moons, and icy debris how does it all add up? Brown believes that Haumea was once larger than it is today, composed half of rock and half of frozen water. Sometime between 3.5 billion and 4.5 billion years ago, Haumea was involved in a collision with another object. The impact released the energy equivalent of 10 billion nuclear bombs exploding. It blasted the two icy moons and the chunks of smaller icy debris off Haumea and accelerated its spin rate. Today, says Brown, Haumea resembles an orbiting M&M candy a small, rocky object covered in a thin shell of ice. The Haumea collision wasn t the only crack-up in the solar system s early history. Astronomers believe that a Mars-sized object called Theia smashed into the young Earth some 4.5 billion years ago. The impact ejected chunks of rock into space that gradually accreted (fused) to form an orbiting satellite with enough gravity to acquire a round shape and become the moon. The still-existing debris around Haumea promises to reveal more about the process of what happens when worlds collide, says Brown. As old as Haumea is, its story is far from over. The enormous gravity of Neptune could one day throw Haumea like a boomerang through the solar system. At that point, it will become a comet that burns as brightly as a full moon when it passes Earth. When might that happen? Maybe a billion years from now, says Brown. So you have a little bit of waiting to do, he says. Article: Copyright 2010 Weekly Reader Corporation. All rights reserved. Weekly Reader is a registered trademark of Weekly Reader Corporation. Used by permission. 2

3 Non-fiction: Way-Out World BSIP/Photo Researchers, Inc.; Inset: NASA Ring around the Planets The plutoid Haumea is located in the Kuiper belt, a ring of small bodies that extends far beyond Neptune. The bodies, which number in the billions, are remnants from the early years of the solar system when a giant cloud of gas and dust began to coalesce (stick together). That coalescence resulted in objects ranging in size from the small members of the Kuiper belt and the asteroid belt to the planets. Haumea is about 1,450 kilometers (900 miles) wide; Pluto, about 2,300 kilometers (1,400 miles). 3 Article: Copyright 2010 Weekly Reader Corporation. All rights reserved. Weekly Reader is a registered trademark of Weekly Reader Corporation. Used by permission.

4 Questions: Way out World Name: Date: 1. According to the passage, how much force was in the explosion that created Haumea? A the force of 2 million nuclear bombs B the force of 10 million nuclear bombs C the force of one bomb D the force of 10 billion nuclear bombs 2. The passage describes the creation of Haumea. How many years ago did Haumea collide with another object? A between 7.0 and 8.5 billion years ago B between 5.5 and 6.5 billion years ago C between 3.5 billion and 4.5 billion years ago D 10 billion years ago 3. Based on the passage, how do advances in telescope technology most likely change what astronomers know about space? A advances in telescope technology are more expensive B advances in telescope technology help them see better C advances in telescope technology help them hear better D advances in telescope technology help them draw maps 4. Read the following sentence: When an object in space rotates that rapidly, it stretches the way pizza dough does when it s tossed and twirled in the air, says Brown. As used in the passage, rapidly means A randomly B in a pattern C slowly D quickly 5. This passage is mostly about A the creation of Haumea after a collision B reclassifying Pluto as a dwarf planet, then as a plutoid C how Haumea was named D how scientific knowledge about the solar system is constantly changing 1

5 Questions: Way out World 6. What were Haumea s moons named after? 7. Based on the passage, why did scientists most likely rename Haumea? 8. The question below is an incomplete sentence. Choose the word that best completes the sentence. Pluto was thought to be the ninth planet scientists reclassified it as a dwarf planet. A after B but C before D so 9. Answer the following questions based on the sentence below. In 2007, the International Astronomical Union reclassified Pluto as a dwarf planet because its gravity isn t as strong as most planets. What? the International Astronomical Union (did) What? When? Why? 2

6 Questions: Way out World Directions: Read the vocabulary word and definition below to complete questions 10a, 10b, and 11. Vocabulary Word: collide (col lide): to crash. 10a. Read the sentences below and underline all forms of the word collide. 1. Objects in space often collide with a lot of force, causing pieces of planets to break off when they hit each other. 2. Hockey players will often collide into each other on the ice when they are trying to get the puck. 3. The bumpy sidewalk caused the roller skaters to collide with each other and bump their heads together. 4. The drivers were not paying attention, causing the cars to collide. 5. The biker ignored the stop sign, causing a car to turn suddenly and collide with a tree. 10b. Which image best demonstrates the word collide? 11. In which of the following sports do players often collide with each other: football or tennis? Why? 3

7 Teacher Guide & Answers: Way-Out World Teacher Guide and Answers Passage Reading Level: Lexile 980 Featured Text Structure: Descriptive the writer explains, defines or illustrates a concept or topic Passage Summary: This passage describes the creation of Haumea, a plutoid, as the result of a collision. The passage describes Haumea, how it was classified and named, and how studying this plutoid can help scientists learn more about what happens when worlds collide. 1. According to the passage, how much force was in the explosion that created Haumea? A the force of 2 million nuclear bombs B the force of 10 million nuclear bombs C the force of one bomb D the force of 10 billion nuclear bombs 2. The passage describes the creation of Haumea. How many years ago did Haumea collide with another object? A between 7.0 and 8.5 billion years ago B between 5.5 and 6.5 billion years ago C between 3.5 billion and 4.5 billion years ago D 10 billion years ago 3. Based on the passage, how do advances in telescope technology most likely change what astronomers know about space? A advances in telescope technology are more expensive B advances in telescope technology help them see better C advances in telescope technology help them hear better D advances in telescope technology help them draw maps 4. Read the following sentence: When an object in space rotates that rapidly, it stretches the way pizza dough does when it s tossed and twirled in the air, says Brown. As used in the passage, rapidly means A randomly B in a pattern C slowly D quickly 5. This passage is mostly about A the creation of Haumea after a collision B reclassifying Pluto as a dwarf planet, then as a plutoid C how Haumea was named D how scientific knowledge about the solar system is constantly changing 6. What were Haumea s moons named after? Suggested answer: Haumea s moons are Called Hi iaka and Namaka, named after two of the goddess Haumea s mythical daughters. [paragraph 10] 1

8 7. Based on the passage, why did scientists most likely rename Haumea? Teacher Guide & Answers: Way-Out World Suggested answer: Scientists most likely renamed Haumea because the plutoid broke off from a much larger object. According to Brown, the collision blasted two moons and chunks of smaller icy debris off Haumea. They chose the name because Haumea is the mother goddess in Hawaii whose children came from various parts of her body, which describes Haumea, which is trailed by the small, icy bodies that were once a part of it. [paragraphs 7 & 11] 8. The question below is an incomplete sentence. Choose the word that best completes the sentence. Pluto was thought to be the ninth planet scientists reclassified it as a dwarf planet. A after B but C before D so 9. Answer the following questions based on the sentence below. In 2007, the International Astronomical Union reclassified Pluto as a dwarf planet because its gravity isn t as strong as most planets. What? the International Astronomical Union (did) What? reclassified Pluto as a dwarf planet When? in 2007 Why? because its gravity isn t as strong as most planets To the Teacher: ReadWorks recommends that you teach this vocabulary word to the whole class out loud using the four steps listed below. Vocabulary Word: collide (col lide): to crash. Step 1: Introduce the word a. Teacher writes the word on the board and divides it into syllables: (col lide) b. Teacher says: This word is collide. What is the word? [All students reply together out loud: collide. ] Step 2: Provide a child-friendly definition a. Teacher says: Collide means to crash. b. Teacher says: The passage describes how scientists are interested in what happens when worlds and other objects collide, or crash, in space. Scientists study Haumea because it collided with another object many years ago and broke off into smaller pieces. c. Teacher says: What is the word? [All students reply together out loud: collide. ] 2

9 Teacher Guide & Answers: Way-Out World Step 3: Practice the word Teacher provides examples and additional opportunities to repeat the word. Read the first sentence out loud to your students. Begin reading it again and when you come to the vocabulary word prompt students to say the vocabulary word out loud. Then, finish reading the sentence out loud to your students. Directions: Read the vocabulary word and definition below to complete questions 10a, 10b, and 11. Vocabulary Word: collide (col lide): to crash. 10a. Read the sentences below and underline all forms of the word collide. 1. Objects in space often collide with a lot of force, causing pieces of planets to break off when they hit each other. 2. Hockey players will often collide into each other on the ice when they are trying to get the puck. 3. The bumpy sidewalk caused the roller skaters to collide with each other and bump their heads together. 4. The drivers were not paying attention, causing the cars to collide. 5. The biker ignored the stop sign, causing a car to turn suddenly and collide with a tree. Step 4: Check for student understanding To the Teacher: This step can be completed as a whole class activity or as an independent practice. 10b. Which image best demonstrates the word collide? 11. In which of the following sports do players often collide with each other: football or tennis? Why? Suggested answer: Players often collide with each other in football, because colliding means to crash into something else. Tennis players do not crash into each other usually. Suggested Additional Vocabulary: visible, catastrophic, collision, newfound, advances, perspective, reclassified, appropriate, distinctive, rapidly, squashed, bulges, debris, mythical, equivalent, accelerated, fused, collide, remnants, coalesce 3