Multiple Choice
A particular star shows spectral lines of the lithium isotope ⁶Li.What conclusion do astronomers draw from this observation?
A) The star has vaporized one of its planets that spiraled in too close to the star because the star's own ⁶Li was destroyed by nuclear reactions long ago.
B) The star has not yet begun nuclear reactions in its core because these reactions destroy ⁶Li.
C) Planets must be orbiting around the star because only planets show ⁶Li spectral lines.
D) The star is composed of pristine (unmodified) material from the Big Bang because ⁶Li has been destroyed in material that has been processed in stars and expelled back into space.
Correct Answer:
Verified
Correct Answer:
Verified
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