1. This will/is benefit/benefiting Russia.
I don't get the relevance.
I don't think Russia even has such capabilities and there is no way in hell Iran sells this thing to them.
The next best thing belongs to NK and in theory the Dark Eagle project US has that the DoD claimed to have tested it successfully in 2024 (considering its a Lockheed Martin project, I call it a scam lol).
2. Mach speeds are a misnomer. The speed of sound is lower at higher altitudes. A missile traveling at high altitudes can reach 16 mach much easier than when at lower altitudes. But it will be traveling slower than mach 16 at lower altitudes if it is using the mach 16 of higher altitudes. So, what is the altitude that the mach 16 is measured at?
Mach speed for ballistic missiles is not a misnomer. It gives us a lot of information. For example Mach 16 categorizes this as a High-Hypersonic BM which is impossible to detect or dream of intercepting with existing technology.
As for the altitude, such details are technically classified and aren't published. They called it (and I'm translating) the "traveling speed". And such BMs exit the atmosphere, so you can guess the altitude that way.
Here is another thing to keep in mind, Mach 16 is the speed of the entire missile which weighs about 20 tons (20000 kg). After it reaches its max speed, near the end of its travel distance the booster disconnects and only the much "lighter" warhead remains that weighs 1.5 ton (1500 kg). It has its own engine and it is diving so the gravity is also helping. So unless I'm missing something the warhead itself should dive at a much higher speed than Mach 16, and that's at low altitudes as it reaches its target on the ground.
Is this NASA or Space X?
Neither, its an Iranian long range hypersonic ballistic missile.
