Space & astronomy · the experiment
Measure the Cape Cod Bay superbolide
A 1.6 m rock enters the air at 26 km/s over Massachusetts. Listen to its shock wave to estimate its energy, then bring it down to see what pressure it withstood.
1 · Listen to the shock wave
Beginner
What did the authors base their estimate of about 0.5 kilotons on?
Check it: set the wave's dominant period until you get the article's energy, about 0.5 kt.
2 · Recover the CNEOS figure
Intermediate
The sensors measured 2.92 s. CNEOS reports 1.1 kt, more than twice as much. What period would they have had to measure?
Check it: start from the measured 2.92 s and set the period until you reach the CNEOS energy, 1.1 kt.
3 · Bring the rock down
Expert
An ordinary stone usually breaks up before 5 MPa. On the same path, at 26 km/s, where would it have broken up at the latest?
Check it: at 26 km/s, bring the rock down until the dynamic pressure reaches 5 MPa.
4 · What if it were slower?
Expert
Same rock, same terminus at 33.6 km, but arriving half as fast, at 13 km/s. What pressure would it have withstood there?
Bolide measured
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