Multiple Choice
What is the significance of the object Sagittarius A* ("Sagittarius A-star") in our Galaxy?
A) It appears to be a jet of material ejected from an accretion disk around a supermassive black hole in the galactic nucleus.
B) It 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) It is a bright,high-speed cloud of gas close to the galactic nucleus,which allows the mass of the nucleus to be calculated.
D) It appears to be the actual nucleus of the Galaxy.
Correct Answer:
Verified
Correct Answer:
Verified
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