Multiple Choice
Some "superstars" give off more than 50,000 times the energy of the Sun. Why are there no such stars among the stars that are close to the Sun?
A) because conditions in the "neighborhood" of the Sun only permit low-mass (low luminosity) stars to form
B) because such very luminous stars are extremely rare, and thus any small neighborhood in the Galaxy is unlikely to contain one of them
C) because all stars in the vicinity of the Sun have planets, and planets rob a star of its brightness
D) because such superstars only give off a lot of energy for a year or so, before they die
E) because such superstars are really several hundred stars blending their light together (but so far away we can't distinguish individual stars) ; nearby stars are easy to separate
Correct Answer:

Verified
Correct Answer:
Verified
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