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During the T-Tauri phase of a protostar, it |
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Definition
may develop very strong winds |
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What is the critical core temperature required for fusion |
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Which statement about the stages of starbirth is false |
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nuclear reaction begin in the core by stage 4 |
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On an H-R diagram a protostar would be |
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Definition
above and to the right of the main sequnce |
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Term
The single most important determinant of the temp, density, radius, luminosity and pace of evolution of a protostar is its |
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A cloud fragment too small to collapse into a main sequence star becomes a |
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All globular clusters in our milky way are how old |
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around 10 billion years old |
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What are star clusters ideal laboratories for stellar evolution |
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Definition
their stars are all about the same age, composition and distance from us |
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Which of these would typically be the brightest star in a young open cluster |
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What are the characterists of an open cluster of stas |
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a few hundred, mostly main-sequence stars |
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Which of these would be the brightest star in an ancient globular cluster |
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Definition
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Which is a characteristic of globular star clusters |
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Definition
old age and hundreds of thousands of stars, only about 50pc wide |
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Term
How long does it take an M-type star to reach the main sequence, compared to a solar type starÉ |
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Definition
about twenty times longer |
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Term
A fragment of collapsing gas cloud that ocmes to equilibrium with a central temperature of 4 million K will become a |
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Definition
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Term
Why are the majority of stars in the sky in the main sequence phase of their lives |
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Definition
this is the longest lasting phase in each star`s life |
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Which statement about the rate of stellar evolution is true |
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Definition
The more massive the original star, the faster the evolution |
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Which of the following are not very young stars of prestellar objects |
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Within a globular cluster, what would you expect to find in the population of stars |
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many red giants, white dwarfs and dim red stars but no bright blue stars or dust and gas |
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In which stage of evolution is a star formed |
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In what stage of evolution is the forming star the brightest |
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What is the importance of nebular clouds that surround newly forming stars |
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Definition
they add mass to the star during formation |
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What is not true of successful star formation |
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Definition
planets are formed out of the nebular cloud |
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