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Home Q & A Board Science-Related Homework Help Physics
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symbo symbo
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7 years ago
Measurements from distant galaxies indicate that supernovae should occur at a rate of five per century in a spiral galaxy such as the Milky Way, but only three have been recorded in this Galaxy in the past 1000 years. Why is this?
A)   Most supernovae produce X rays and radio waves, not visible light, and were hence invisible to earlier observers.
B)   The majority of supernovae must have occurred in the plane of the Milky Way and hence were hidden from the Earth by the dense gas and dust in the Milky Way plane.
C)   The Milky Way Galaxy is somehow different, with much lower numbers of very massive stars in general, so many fewer stars have undergone supernova explosions.
D)   Observers were not watching the sky carefully enough, particularly through the Dark Ages and over the past few centuries.
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Discovering the Universe

Discovering the Universe


Edition: 7th
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hyponoticahyponotica
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symbo Author
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7 years ago
Brilliant ツ
ky
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Yesterday
Just got PERFECT on my quiz
bkrandy
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2 hours ago
I appreciate what you did here, answered it right Smiling Face with Open Mouth
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