DO NOT EDIT--Changes must be made through “File info” CorrectionKey=NL-A Our Star, the SUN DO NOT EDIT--Changes must be made through “File info” DO NOT EDIT--Changes must be made through “File info” CorrectionKey=NL-A CorrectionKey=NL-A Read Preview — Flip through the book. to Look for words that are new, and share them with a partner. Our Star, Learn 1. observatory A room or building housing an astronomical telescope or other the scientific equipment for the study of natural phenomena. 2. pinhole projector A device used to safely view an image of the sun. SUN Skim — Look at the illustrations and photos. What is happening in the story? Credits: 7 ©solarseven/Shutterstock; 10 ©NASA/A. Lutkus/H. Zell. Can you tell what it will be about? Copyright © by Houghton Mifflin Harcourt Publishing Company All rights reserved. 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ISBN 978-0-358-39412-9 Read — Read to learn how scientists 1 2 3 4 5 6 7 8 9 10 XXXX 29 28 27 26 25 24 23 22 21 20 study the sun, our closest star, without 4500000000 damaging their eyes. r8.20 If you have received these materials as examination copies free of charge, Houghton Mifflin Harcourt Publishing Company retains title to the materials, and they may not be resold. Resale of examination copies is strictly prohibited. GO Possession of this publication in print format does not entitle users to convert this publication, or any portion of it, into electronic format. InCopy Notes 1. This is a list InCopy Notes 1. This is a list DO NOT EDIT--Changes must be made through “File info” DO NOT EDIT--Changes must be made through “File info” CorrectionKey=NL-A CorrectionKey=NL-A “Wow, I can see so many stars!” Asha exclaimed to her father as she gazed up at the night sky in wonder. “We definitely never see this many stars in the city.” The two had traveled outside the city limits to try out Asha’s brand-new telescope. It had taken her months to save up enough of her weekly allowance to buy it, and she couldn’t wait to peer through the eyepiece at the constellations above. Asha carefully angled the telescope toward a constellation, and then she looked through the eyepiece. “I can see Betelgeuse so clearly,” she said to her father as she identified the star. “It’s part of the constellation Orion, which we learned about in school last week. Did you know that Betelgeuse is 700 times the size of the sun?” “No, I didn’t know that,” said her father. “Which one is it?” he asked, taking a turn at the telescope. “It’s the reddish star,” Asha replied. “It makes up the left shoulder of Orion, named after a hunter in Greek mythology. Astronomers study stars like Betelgeuse by looking through telescopes, but stars we see in the night sky are very far away. I know that our star, the sun, is much closer to Earth and therefore dangerous to look at directly. I wonder how scientists safely study the sun.” 2 3 DO NOT EDIT--Changes must be made through “File info” DO NOT EDIT--Changes must be made through “File info” CorrectionKey=NL-A CorrectionKey=NL-A It was a beautiful, bright, and sunny day in the city as Asha and her family walked onto the grounds of the large and imposing astronomical observatory. “This place is huge!” Asha exclaimed in amazement. “Where do you think we should start?” She noticed a map showing the building’s layout. “Oh, look,” she said as she studied the map, “there’s a solar observatory! Mom and Dad, could we go there first?” The next morning at breakfast, Asha’s mother said, “Your father told me you two saw a lot of cool stars last night.” “We did!” Asha replied enthusiastically. “We could see so many details with my new telescope.” “Well, perhaps we should spend the day at the local observatory so we can all learn about the stars,” her mother suggested. “Yeah, I want to learn about stars too!” cried Maya, Asha’s little sister. “Could we really, Mom?” Asha asked, excited. “I have some questions about how scientists study the sun. I think a trip to the observatory would help answer my questions.” 4 5 DO NOT EDIT--Changes must be made through “File info” DO NOT EDIT--Changes must be made through “File info” CorrectionKey=NL-A CorrectionKey=NL-A Asha and her family wandered into the main level of the “That’s right!” Soheila said approvingly. “The distance building, looking all around delightedly. between Earth and our sun is about 150 million “Welcome to our observatory,” a smiling young woman kilometers. Can anyone tell me why the sun is important greeted them. “My name is Soheila Tayeb, and I am a to life on Earth?” volunteer here. I am a student at the local university, “Because it makes Earth warm and livable,” someone in where I am studying astronomy, and today I am giving a the crowd said. presentation about the sun. Would you like to join us?” “Because it provides light,” someone else called out. “Oh, yes!” Asha replied, as she walked beside Soheila into “Because plants use light from the sun to make food a large room, with the rest of Asha’s family close behind. and oxygen for life on Earth,” Asha said confidently. She “Hello, everyone,” said Soheila to the group that had had learned that fact in science class. gathered. “I will start by asking: What do you know about “Those are all great answers,” Soheila said, nodding our sun?” her head. Asha raised her hand eagerly. “I know that it is our nearest star,” she said. 6 7 DO NOT EDIT--Changes must be made through “File info” DO NOT EDIT--Changes must be made through “File info” CorrectionKey=NL-A CorrectionKey=NL-A “My dad and I looked at Betelgeuse last night through my telescope,” Asha told Soheila. “I know that I can observe the stars at night safely through a telescope, but how do scientists look at the sun without hurting their eyes?” she asked. “That is a great question!” Soheila replied. “Our sun is an average-sized star,” Soheila said, “but there are many stars that are smaller in size and many that are much, much larger. For example, Betelgeuse, a star in the Orion constellation, is a red supergiant star. Its diameter is 700 times the diameter of the sun.” Soheila gestured toward a model of relative sizes. She continued, “The largest star is UY Scuti, and it is about 1700 times the size of our sun. The smallest stars are about a tenth the size of our sun.” 8 9 DO NOT EDIT--Changes must be made through “File info” DO NOT EDIT--Changes must be made through “File info” CorrectionKey=NL-A CorrectionKey=NL-A “This illustration shows one of the solar observatories in space,” Soheila said. “SOHO, or the Solar and Heliospheric Observatory, is a collaboration between the European Space Agency and NASA to study the interior and exterior of the sun. It was launched into space in 1995. Another solar observatory is the SDO, or Solar Dynamics Observatory, which was launched by NASA in 2010 to study how solar activity is generated and how solar variation affects life on Earth. Both observatories provide data and images of the sun. Scientists on Earth can also study the sun using telescopes with special filters to protect their eyesight.” Soheila smiled proudly and stated, “Here in this solar observatory, we have three solar telescopes that use light coming through a special mirrored device in the overhead dome to provide live views of the sun, which you can see here. Those dark spots you see on the image of the sun are called sunspots, which are areas of slightly cooler temperature on the surface of the sun. Scientists use sunspots to track the rotation of the sun.” 10 11 DO NOT EDIT--Changes must be made through “File info” DO NOT EDIT--Changes must be made through “File info” CorrectionKey=NL-A CorrectionKey=NL-A “Is there a safe way for me to observe the sun at home?” Asha queried. “There is indeed,” Soheila replied. “You can make a pinhole projector to safely view an image of the sun. If you search online, you will find instructions for how to build one.” “Thanks, Ms. Tayeb, I’m definitely going to do that!” Asha replied excitedly. “I’m so glad we came to the observatory today, because I learned a lot about the sun.” “You’re very welcome,” Soheila said. “Please enjoy the rest of your visit to the observatory.” Asha, Maya, and their parents spent the rest of the afternoon wandering through the observatory’s various exhibits and learning more about astronomy. The next day, Asha couldn’t wait to build her own pinhole projector for viewing the sun.