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The Sun, Yellow Dwarf Star at the Heart of the Solar System NASA.Gov, Adapted by Newsela Staff

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The Sun, Yellow Dwarf Star at the Heart of the Solar System NASA.Gov, Adapted by Newsela Staff Name: ______________________________ Period: ______ Date: _____________ Article of the Week Directions: Read the following article carefully and annotate. You need to include at least 1 annotation per paragraph. Be sure to include all of the following in your total annotations. Annotation = Marking the Text + A Note of Explanation 1. Great Idea or Point – Write why you think it is a good idea or point – ! 2. Confusing Point or Idea – Write a question to ask that might help you understand – ? 3. Unknown Word or Phrase – Circle the unknown word or phrase, then write what you think it might mean based on context clues or your word knowledge – 4. A Question You Have – Write a question you have about something in the text – ?? 5. Summary – In a few sentences, write a summary of the paragraph, section, or passage – # The sun, yellow dwarf star at the heart of the solar system NASA.gov, adapted by Newsela staff Picture and Caption ___________________________ ___________________________ ___________________________ Paragraph #1 ___________________________ ___________________________ This image shows an enormous eruption of solar material, called a coronal mass ejection, spreading out into space, captured by NASA's Solar Dynamics ___________________________ Observatory on January 8, 2002. Paragraph #2 Para #1 The sun is a hot ball made of glowing gases and is a type ___________________________ of star known as a yellow dwarf. It is at the heart of our solar system. ___________________________ Para #2 The solar system consists of everything that orbits the ___________________________ sun. The sun's gravity holds the solar system together, by keeping everything from planets to bits of dust in its orbit. If it weren't for Paragraph #3 the sun, our planet would simply fly off loose into the universe. ___________________________ Para #3 The sun is responsible for the Earth's seasons, ocean ___________________________ currents, weather and climate. Though it is special to us, there are billions of stars like it scattered across the Milky Way. ___________________________ Paragraph #4 93 Million Miles From Earth ___________________________ Para #4 The distance from the center of the sun to its outer edge is ___________________________ 432,168.6 miles. It is not an especially large star — many are several times bigger. However, it is still far, far bigger than our ___________________________ home planet. It would take 1.3 million Earths to fill up the space the Paragraph #5 sun occupies. ___________________________ Para #5 The sun is around 93 million miles from Earth. Paragraph #6 The Milky Way Galaxy ___________________________ Para #6 The sun is located in the Milky Way galaxy, a vast system ___________________________ containing at least 200 billion stars. It orbits the center of the Milky Way. As it travels, it brings planets, asteroids and other objects in ___________________________ the solar system along with it. Paragraph #7 Para #7 The solar system moves through the Milky Way at an average speed of 450,000 miles per hour. Even at this speed, one ___________________________ complete orbit around the Milky Way takes around 230 million ___________________________ years. As the sun travels, our Earth and all the other planets go along for the ride. ___________________________ Para #8 The sun rotates or turns as it orbits the center of the Milky Paragraph #8 Way. Since the sun is not a solid body, different parts rotate at different rates. At its center, the sun spins around once about ___________________________ every 25 days, while at its poles it rotates once every 36 days. ___________________________ Sun Formed 4.5 Billion Years Ago ___________________________ Para #9 The sun formed from a giant, rotating cloud of gas and Paragraph #9 dust about 4.5 billion years ago. Like all stars, it will someday run out of energy. When the sun starts to die, it will grow so large it will ___________________________ eat up Mercury and Venus and maybe even Earth. Scientists ___________________________ believe the sun will live for around another 6.5 billion years. ___________________________ Made Of Hydrogen, Helium Paragraph #10 Para #10 The sun is around 71 percent hydrogen and 27 percent helium. ___________________________ ___________________________ Para #11 It has six regions. Its inside is made up of the core, the radiative zone and the convective zone. Its outside consists of the Paragraph #11 visible surface, or photosphere, the chromosphere, and the outermost region, or corona. ___________________________ Para #12 At the core, the temperature is about 27 million degrees ___________________________ Fahrenheit. In the connective zone, the temperature drops down to Paragraph #12 below 3.5 million degrees. The surface of the sun — the part we can see — is about 10,000 degrees Fahrenheit. That is much ___________________________ cooler than the blazing core, but it is still hot enough to make diamonds not just melt, but boil. ___________________________ ___________________________ Paragraph #13 Sunlight To Earth In 8 Minutes ___________________________ Para #13 The surface of the sun, or photosphere, is a 300-mile-thick region. It is not a solid surface like the surface of a ___________________________ planet, but simply the outer layer of the gassy star. ___________________________ Para #14 We see radiation from the photosphere as sunlight. It Paragraph #14 reaches Earth about eight minutes after it leaves the sun. ___________________________ Chromosphere And Solar Eclipses ___________________________ Para #15 Above the photosphere lie the wispy chromosphere and the corona, or crown. Together, these make up the thin solar Paragraph #15 atmosphere, or the layer of gasses that surround the sun. ___________________________ Para #16 Visible light from these top regions is usually too weak to ___________________________ be seen against the brighter photosphere. However, when the moon covers the photosphere in a solar eclipse these regions do ___________________________ become visible. The chromosphere looks like a red rim around the sun, and the white corona looks like a beautiful ring of flowers. Paragraph #16 ___________________________ Sunspots, Solar Flares ___________________________ Para #17 Electric currents in the sun generate a powerful magnetic field. The field is carried out through the solar system by solar wind. ___________________________ Solar wind is a stream of electrically charged gas that blows outward from the sun in all directions. Paragraph #17 ___________________________ Para #18 About every 11 years, the sun's geographic poles change their magnetic polarity — the negative pole becomes the positive ___________________________ pole, and vice versa. When this happens, the surface of the sun becomes violently active. Sunspots occur and solar flares shoot out ___________________________ into space. These events can disrupt satellites and other communication devices. Our TV may not work, our cell phones will Paragraph #18 be down, a high-speed train may run loose and if an astronaut ___________________________ happens to be on the moon at the time when the sun erupts, he or she would be in great danger. ___________________________ Ancient Myths And Superman ___________________________ ___________________________ Para #19 The sun has inspired mythological stories in cultures around the world, including those of the ancient Egyptians, the Paragraph #19 Aztecs of Mexico, Native American tribes of North and South America, the Chinese, and many others. ___________________________ Para #20 If you're Superman (or a fellow Kryptonian), your powers ___________________________ are heightened by the yellow glow of our sun, and you can even dispose of dangerous materials like Superboy once did, by hurling ___________________________ them into the sun. Paragraph #20 ___________________________ ___________________________ TURN TO BACK PAGE FOR QUESTIONS QUIZ Standard 1: What the Text Says 1. Which section of the article highlights what will happen to the sun in the future? (A) The Milky Way Galaxy" (B) "Sun Formed 4.5 Billion Years Ago" (C) "Sunlight To Earth In 8 Minutes" (D) "Ancient Myths And Superman" Standard 1: What the Text Says 2. Select the sentence from the section "The Milky Way Galaxy" that demonstrates the force of the sun's gravity. (A) The sun is located in the Milky Way galaxy, a vast system containing at least 200 billion stars. (B) As it travels, it brings planets, asteroids and other objects in the solar system along with it. (C) Even at this speed, one complete orbit around the Milky Way takes around 230 million years. (D) Since the sun is not a solid body, different parts rotate at different rates. Standard 4: Word Meaning and Choice 3. Read the FIRST PARAGRAPH of the article. The sun is a hot ball made of glowing gases and is a type of star known as a yellow dwarf. It is at the heart of our solar system. Based on the article, why does the author compare the sun to a "heart"? (A) because it is unique among billions of stars in our galaxy. (B) because it forms a similar shape as it moves in its orbit (C) because it is the force that gives energy to our solar system (D) because many cultures have shown their love for the sun Standard 4: Word Meaning and Choice 4. Read the sentence from the section "The Milky Way Galaxy." The sun is located in the Milky Way galaxy, a vast system containing at least 200 billion stars. Which option is the BEST definition of the word "vast" as used in the sentence? (A) cloudy (B) traveling (C) empty (D) enormous .
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