Moon formation evidence that Moon material underwent high-temperature processing is best described by which statement?

• A. Moon formed at high temperature during a giant impact, causing volatile loss
• B. Moon formed from cold accretion
• C. Moon captured from outer solar system
• D. Moon's material identical to Earth's crust

Answer: (A)

High-temperature processing in lunar material points to a formation event that heated and melted the material before the Moon assembled. The most supported scenario is a giant impact: a Mars-sized body collided with early Earth, ejecting a hot disk of molten and vaporized material that cooled and coalesced into the Moon. Heating during that event would drive off some volatile elements, leaving lunar rocks depleted in volatiles relative to Earth. This volatile loss is a key clue that the Moon formed from hot debris rather than from cold, untouched material. The idea that the Moon formed from cold accretion doesn’t explain the volatile depletion, and capture would require a different origin and usually different isotopic fingerprints. Saying the Moon’s material is identical to Earth’s crust overstates the similarity, since the Moon’s rocks and crust show distinct histories and compositions shaped by the high-temperature formation process.