questions and verified answers covering
stellar evolution, galaxies, cosmology, and
advanced astronomy concepts.
Parsecs are used to measure:
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A) Distance
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B) Time
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C) Speed ......answer.....A
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Star A is seen at a parallax angle of 0.2 arcsec while Star B at an angle of
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1.2 arcsec. Which star is further away and by how much/less?
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,A) Star A is 6 times further away
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B) Star B is 6 times away
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C) Star A is 10 times further away
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D) They are both at the same distance ......answer.....A
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Mars is approximately twice as far from the Sun as Venus. How much
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dimmer does the Sun appear from Mars?
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A) Half as bright
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B) One third as bright
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C) One quarter as bright
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D) One sixteenth as bright ......answer.....C
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,Two stars have the same temperature and luminosity, but one is 10 lig
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ht years from the Earth, and the other is 1000 light years away. The m
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ore distant star appears to be
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A) 10x fainter
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B) 100x fainter
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C) 10,000x fainter
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D) 100,000,000x fainter
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E) The same brightness ......answer.....C
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α Fic has the same mass as the Sun, but is about 100x more luminous. If
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the Sun has a total lifetime around 10 billion years, how long would yo
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u expect α Fic to live, to the nearest power of ten?
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, Hint: For stars of the same mass, the life-
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time ranges as one over the star's luminosity (i.e. the more luminous s
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tars live shorter lives).
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A) 100 billion years
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B) 1 billion years
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C) 10 billion years
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D) 100 million years
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E) 1000 billion years ......answer.....D
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The apparent brightness of a star is 3 x 10^-10 W m-
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2 and it's parallax 0.05 arcsec. Estimate the star's lifetime as compare
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d to that of the sun. Round up your final answer.
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