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Home Q & A Board Science-Related Homework Help Physics
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staedtler staedtler
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7 years ago
What observations convince us that the energy source of a quasar is physically very small?
A)   Rapid fluctuations in brightness since variations over 1 day mean that the source must be less than one light-day across
B)   The instant disappearance of the quasar when occulted by the Moon's edge as the Moon moves in front of a quasar, indicating a very small source size
C)   The sharpness of the emission lines in their optical spectra since motions within a large source would smear out the line shapes
D)   The extremely small size of the image of a quasar, even from Hubble Space Telescope images and radio interferometry measurements
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Discovering the Universe

Discovering the Universe


Edition: 7th
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hyponoticahyponotica
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7 years ago
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staedtler Author
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7 years ago
Grinning Face Exactly what I needed
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