alleryStart learning →Earth was struck as often as the Moon, yet shows far fewer craters. What removed them?
AA shield from our magnetism
BA gap in the asteroid belt
CActive geology on our planet
DThe pull of the giant planets
Answer & Solution
Correct answer: C. Active geology on our planet
1. The Moon is close by, so both worlds were hit at about the same rate.
2. Earth's crust is constantly renewed by plate tectonics and worn down by erosion.
3. Craters are erased faster than new ones form, so few survive to be counted.
4. A magnetic field deflects charged particles, not solid rock, so it offers no shield.
_Source: OpenStax Astronomy (CC BY 4.0), section 8.5 Cosmic Influences on the Evolution of Earth_
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