Los Alamos Scientist's Insights on the GBU-57 Ordnance Penetrator

they each drop a weapon that can vector itself to a very highly accurate position in a mountain, and you can penetrate with one and blow a hole, and then all of that material is suspended. And you have another one come in immediately afterwards and penetrate through much softer material, until you get into hard material, and you penetrate that, and then you explode, and you levitate all that material. Then you bring a third one in after it, you could start thinking about digging really deeply in

Incredible that they have the accuracy to hit the same hole repeatedly, digging further and further down with each subsequent drop.