David Bober

So a typical experiment for us would be we may be measuring the speed of a shockwave as it transits through a sample.

So we'll measure very precisely the moment of impact.

And then we'll measure how long it takes for that shockwave that's generated to transit across the sample.

And that tells us something important about the thermodynamic state.

Like imagine a snowplow driving down the street.

The snow has fallen overnight.

The road is covered in a nice even layer of it.

As the snowplow goes, the snowplow blade moves at a certain velocity and the snow piles up in front of it and it compacts.

And as it compacts, you can imagine that wave starts to move forward away from the plow.

So the farther the plow moves, now there's this wave traveling forward of compacted snow.

That disturbance is what we're looking at, where you go from unmoved snow to compacted slab.

And when you do that, it makes an astounding mess.

When a projectile hits something going at kilometers per second, people sometimes ask me what's left afterwards.

What's left is almost nothing.

The target's essentially exploded.

So you've taken your target, you've in some cases vaporized it, you've mixed it with soot, everything else is more or less burned, and it's embedded as tiny particles around whatever it was in when you shot it.

What makes Jasper really audacious was that the people who conceived of this knew that.

They had experience with those sorts of gun experiments, and they imagined a way in which they could do it on plutonium and capture every last tiny speck of that material and prevent it escaping into the environment.

If you want to reuse your gun, your containment strategy has to somehow cope with that.

You have to emit the projectile, but not emit the contamination.