Multiple Choice
Aurorae on Earth are caused by
A) electrical currents in the ionosphere,generated by dynamo action in Earth's core.
B) charged particles from the Sun moving through Earth's magnetic field and striking the upper atmosphere.
C) the reflection of sunlight from Arctic and Antarctic ice into the polar night skies.
D) ultraviolet radiation from the Sun ionizing atoms in the upper atmosphere.
Correct Answer:
Verified
Correct Answer:
Verified
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