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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
Why is Cygnus X-1 thought to be a black hole?
A)   It emits X rays that flicker on time scales of one-hundredth of a second, a unique characteristic of a black hole.
B)   No light has ever been observed to come from it.
C)   It is smaller than the Earth, but its mass is too large to be a neutron star or white dwarf.
D)   It has pulled matter from its companion star into an accretion disk around itself.
Textbook 
Discovering the Universe

Discovering the Universe


Edition: 7th
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hyponoticahyponotica
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staedtler Author
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7 years ago
I really appreciate your help!
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