Hypervelocity Fireworks

"Ladies and gentlemen, it's a lovely Fourth of July evening. I've seen fireworks displays in several towns from the radio tower here, and they sure were pretty. But the Nixa Fire Department has promised us a display of what they call hypervelocity fireworks. I can just make out the flashing red light on the top of the tower they've put up, and I think that's ten miles away. Okay, the light is going dim, they must be charging up the electrics, and there it goes! The first projectile is up, looking more like a meteor than any mortar-launched firework, and still it climbs. Wow! It just spread into a shower of sparks like a bunch of flowers, but it looked like it was straight overhead. Jeeze, that must have been twenty miles up! Everybody within the range of this station, go outside and look high into the sky toward Nixa--you WILL be able to see this. There goes another, as the sound of the first one rumbles over me, a sonic boom that goes on and on into the sky. The second firework burst as I was talking, shedding chips of fire and hammering into a streak of green light. Ladies and gentlemen, I always thought that "meteoric rise" was a silly term, but these hypervelocity fireworks are doing just that."

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A projectile fired into the air at sufficiently high speed will burn up. A variety of electromagnetic cannon are capable, at least in theory and development, of launching objects flamingly fast. Hypervelocity, it can be called.

Electromagnetic cannon, since they use magnets, fire metal objects. Different metals, when they burn, give off different colors. This is the basis of hypervelocity fireworks technology.

Early hypervelocity fireworks will be simply metal slugs. Advanced fireworks will use metal rings, which can be around or enclosed in a non-metallic body. Ablative resin layers and insulative ceramics will be used in the advanced designs.

Designers of hypervelocity fireworks will experiment to achieve various effects. Liquids and solids of all kinds can be packed into a shell. Mixtures, shapes and arrangements of materials can create different patterns. Large fireworks of the gunpowder sort could be launched in an insulated shell.

A hypervelocity launch tower will be tall, to allow the shockwave of a launched projectile to travel outward above ground level. Spectators will not need to be close, as a carefully-designed hypervelocity firework will burn up as high as forty miles above the ground, like a meteor.

The launch tube of a tower will be evacuated of air by a slow pseudo-projectile acting like a pump plunger, and kept evacuated by high-velocity ionized air jets blowing out the muzzle end. If needed, a thin glass dome can be placed over the muzzle of the tube, and broken away as the hypervelocity projectile fires. Alternately, the pseudo-projectile pump can be slow-launched and moved to the side just before a hypervelocity projectile is fired.

Timers may be needed, as the fireworks are travelling upward through thick air into thinner, the opposite of the ideal for self-disintegration. Experimentation and design will be interesting. Aircraft overhead may be in danger.