Multiple Choice
What is the significance of the object Sagittarius A* ("Sagittarius A-star") in the Milky Way Galaxy?
A) Sagittarius A* appears to be a jet of material ejected from an accretion disk around a supermassive black hole in the galactic nucleus.
B) Sagittarius A* is a globular cluster passing close to the galactic nucleus, and the RR Lyrae stars in it allow the distance to the galactic center to be calculated.
C) Sagittarius A* is a bright, high-speed cloud of gas close to the galactic nucleus that allows the mass of the nucleus to be calculated.
D) Sagittarius A* appears to be the actual nucleus of the Galaxy.
Correct Answer:

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Correct Answer:
Verified
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