alleryStart learning →The Moon holds no atmosphere today. What is the basic reason?
AIts surface gravity is too low
BIts surface is far too cold
CIts orbit is far too wide
DIts rotation is far too slow
Answer & Solution
Correct answer: A. Its surface gravity is too low
1. Gas molecules move fast enough to leak away from a small world.
2. The Moon's surface gravity is about one sixth of Earth's.
3. That pull is too weak to hold gas, so any atmosphere escapes or freezes onto the surface.
_Source: OpenStax Astronomy (CC BY 4.0), section 9.1 General Properties of the Moon_
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