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16 Cards in this Set
- Front
- Back
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What is a Star?
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An object in space made of burning gasses, which produce their own light and heat.
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What is Nuclear Fusion?
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The process by which suns produce light and heat (2 Hydrogen atoms combine to form 1 Helium atom)
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What are the 3 Types of Stars?
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• Main Sequence Stars - hottest and largest generate the most light (Sun)
• White Dwarfs - very hot but not bright • Giants and Super Giants - extremely bright but not hot |
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Our Star – The Sun is?
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• Age: 4.6 billion years
• Will last another 5 billion year or so • Type: Main Sequence Star • Size: medium sized star (large for a medium star) • Diameter = 1.4 million km • Composition: 92% Hydrogen and 8% Helium |
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Layers of the Sun?
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• Layers of the Sun
• Core (middle of sun) = 27,000,000 o F _ Nuclear Fusion: the process by which suns produce light and heat (2 Hydrogen atoms combine to form 1 Helium atom) • Convection and Radiation Zones: areas where heat produced in the core of the sun rises to the surface • Photosphere (outer visible layer) = 11,000o F |
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What is a Galaxy?
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A large group of stars, gas and dust held together by gravity.
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Who was the First astronomer to classify galaxies by shape?
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Edwin Hubble.
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What did Edwin Hubble notice.
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Noticed that galaxies were spreading apart
• 3 major types of Galaxies |
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3 Major types of galaxies?
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Elliptical
Spiral Irregular |
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What are Elliptical Galaxies?
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Some elliptical galaxies are nearly circular in shape. Some elliptical galaxies are extremely stretched out, flattened,or elongated.
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What are Spiral Galaxies?
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Galaxies with bright nuclei also had "arms" spiraling out from the middle.
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What are Irregular Galaxies?
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Galaxies that can't be classified as either spiral or elliptical.
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Who noticed The Universe and Big Bang?
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• Edwin Hubble
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What did he notice?
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Noticed galaxies were getting farther apart
o Universe is constantly expanding in all directions |
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What is the Big Bang Theory?
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o 10-20 billion year ago tremendous explosion started expansion of universe from single point.
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What is the Copernican Theory?
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Universe appears the same in all directions.
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