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19 Cards in this Set
- Front
- Back
- 3rd side (hint)
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First stage of the birth of a star is pulling together gas & dust particles by: |
Gravitational Force |
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What happens as gas & dust particles are pulled together? |
Pressure & Temp Increases |
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What makes a star luminous? |
Nuclear fusion of hydrogen nuclei to for helium nuclei |
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Nuclear fusion is the process of what? |
Fusing of two lighter nuclei to form a bigger nucleus emitting large amounts if energy in the process. |
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Plasma consists of: |
Very fast moving nuclei stripped of their electrons |
State of matter |
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At the center of an active star, matter exists in the form of: |
Very high energy plasma |
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Energy produced ar the center of a star----- |
Produces an outward pressure which opposes the gravitational collapse |
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Describe conviction zone in a star. |
Plasma at the bottom of this zone expands from heating & rises to the surface |
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Nuclear fusion at the core of a star releases energy in what form? |
X-rays & Gamma Rays |
2 types of rays |
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What is the thin & spiky layer of gas just outside ofnthe surface of the sun called? |
Chromosphere |
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What are large loops of gas thay extend from tue surface of the sun? |
Prominences |
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What are sunspots? |
Cooler areas on the sun where the magnetic field is strong. |
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Why do massive stars generate much higher Temps at their core? |
Greater gravitational contraction |
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What factors determine how bright a star looks? |
Amount of light produced by the star Size of the star Distance of the star from the earth |
3 things |
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Scale used by astronomers to compare brightness of stars? |
Apparent Brightness |
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Brightest star observed from earth |
Sirius |
Radio co |
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True brightness of stars are measured in...... |
Absolute magnitude |
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Define absolute magnitude for measuring the true brightness of a star. |
Apparent magnitude a star would have if it were placed 10 parsecs from Earth. |
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Most prominent radiation from a very hot star. |
Ultraviolet |
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