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the kinetic energy of the probe was 900 times that of the gravitational binding energy of the moonlet, there is a non-trivial chance that the main thing we'll learn from this mission is how these gravel piles are destroyed via impactors. An important process to solar system development.

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I think I worked it out that the kinetic energy is equivalent to around 2 tonnes of TNT, or of roughly a US Navy Atlanta class light cruiser doing 90 mph down the freeway.

Good unit of measurement, that last one.

> 900 times that of the gravitational binding energy of the moonlet

Wait, seriously? Maybe I should have paid more attention to the relative scale of these things. That makes it sound like the most reasonable expected outcome is total obliteration.

The mission was approved in 2015, which means it was designed before then, we've learned a good chunk about how smaller asteroids bind together since then, the hyabusa 2 and osiris rex missions were both after 2019, so it wasn't wholely unreasonable that some other kind of internal binding mechanism might be at play besides the piddling role gravity plays at these scales.

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