The Tunguska body carried the punch of a 5-megaton bomb, yet dug no crater. What explains that?
AIt struck a deep ocean basin
BIt broke apart before landing
CIt was far too small to dig one
DIt came in at a low angle
Answer & Solution
Correct answer: B. It broke apart before landing
1. A crater needs the incoming body to reach the ground still in one piece.
2. The Tunguska object was stony and weighed roughly 10,000 tons.
3. Air pressure shattered it about 8 kilometers above the surface.
4. Only heat and shock reached the ground, so no pit was excavated.
5. The blast still flattened more than a thousand square kilometers of forest.
6. Siberia is dry land, so a deep ocean basin was never involved.
7. At about 40 meters across the body was large enough to dig a crater had it survived.
8. Angle does not matter here, since impact craters come out circular at any approach angle.
_Source: OpenStax Astronomy (CC BY 4.0), section 8.5 Cosmic Influences on the Evolution of Earth_
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