Space & astronomy · the experiment
Silence the Moon
A Moon that keeps shaking for hours, empty cracks where waves bounce, thirteen Apollo crashes to settle it. Four questions, from beginner to expert.
1 · Find what makes the Moon ring
Beginner
According to this model, what makes the lunar coda last so long?
2 · Double the crack density
Reference model: 85 cracks 1 km long over an area of 850 km². Density ε = (N / A) × (L / 2)², that is 0.025. A variant doubles the density to 0.05, with the same length and the same area.
Intermediate
How many cracks does this variant contain?
3 · Estimate the size of the cracks
Correlation between simulated and observed envelopes: about 0.85 for cracks 0.5 to 2 km long, about 0.64 for 4-km cracks.
Expert
What do the authors conclude about the length of the cracks?
4 · Compare seismology and radar
The radars of the Chang'e rovers usually probe less than 500 metres below the surface.
Expert
What does Apollo seismology, reread with this model, add?
Moon quieted
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