Multiple Choice
Much of the mass of the Milky Way Galaxy appears to be in the form of "dark matter" of unknown composition. At present, dark matter can be detected only because
A) it emits synchrotron radiation at radio wavelengths.
B) its gravitational pull affects orbital motions in the Galaxy.
C) it bends light from distant quasars.
D) it blocks out the light from distant stars in the plane of the Galaxy.
Correct Answer:

Verified
Correct Answer:
Verified
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