When the Russians initially hit Yuzhmash with the “Hazel” MIRV impactors, I think the NATO guys went there to inspect the debris, a standard measure when some new weapon is suspected to have been used. I think their first reaction was professional and “business as usual”. By now, I think they are all holding their heads in shock.

You see, what happened there is something that would not be intuitive to non-physicists. People normally imagine physical matter behaving in certain ways, which is why I periodically hear the question “why are all the craters on the Moon round and not elliptical, when one would expect most impacts to happen at oblique angles?” Well, you see, what happens at such high-velocity impacts, is well outside of normal human experience. We expect there to be a great deal of a difference between rock and water, and we don’t intuitively think in terms of energies that far exceed the energy of the molecular bonds, but when an asteroid strikes an object, what actually happens is that the kinetic energy of the object converts into thermal energy, which is a fancy way of saying that both the object and the immediate impact zone are either liquefied or evaporated, depending on the energy level they receive and whether it’s water ice, rock or iron. But, basically, both the impactor and the impact zone turn to a liquid that spherically explodes outwards and sprays liquid rock, glass, water vapour, various gases and molten metal outwards:

So, the round crater isn’t from the meteorite. The meteorite was liquefied/evaporated on impact, together with the impact zone. The crater was from the liquid explosively propelled outwards from the area, the way steam would disintegrate a failed pressure cooker.

The impact velocity of the meteors striking Earth is around 12 km/s. This is around 3-4 times faster than the impact velocity of the “Hazel” penetrators. I heard that the temperature of the impactors before they hit was around 3000°C. This means that they are made from either Tungsten, or some kind of a Tungsten alloy. This means they are very dense, and have greater kinetic energy and structural integrity than an asteroid impacting at this velocity, and they are also shaped like needles, which would create greater pressure on the ground, causing deeper penetration. I don’t know how deep they went, but I would expect 10-50m. On the surface level, I would expect lots of percussive damage to the concrete structures, but not much energy was transferred yet. As the impactor goes deeper, it grows hotter, as some kinetic energy is converted into heat. At a certain critical point, the force required to penetrate deeper becomes greater than the cohesive forces within the impactor, and its entire remaining kinetic energy is converted to heat, adding to the initial 3000°C. Let’s say that the melting point of concrete is the highest melting point of its compounds, which is limestone at 2570°C and quartz at 1650°C. This means that, at the end of the road for each Tungsten impactor there would be a spherical cavity caused by the explosion of overheated materials, consisting of various vapours, molten rock, molten glass and molten Tungsten, which probably remained hot for days after the impact. That stuff wasn’t just pierced and shredded. No, the deepest levels of the structure were turned into something similar to the Trinitite formed after the Trinity nuclear explosion in New Mexico, or tektites that shower the Earth thousands of kilometers across with globules of molten glass after an asteroid strike.

So, those inspectors are holding their heads there in shock, because they did the math and concluded that this would turn their deepest command bunkers into a lake of fire and brimstone. In some ways, this is worse than a nuclear bomb, because it’s so deep, so precise, and destruction is total.