To invest wisely in the likelihood that originators can capitalize on a string of fads through creativity and experimentation is very different from investing in one hot rocket that goes straight up with full knowledge that gravity will send it back down with equal and opposite thrust.

FORBES: Don't Fear the Fad

The latter include, for example: supercomputers, advanced machine tools, fiber optic and other sophisticated telecommunications gear, jet engine hot sections, rocket propulsion and guidance components, "stealth" technology, to name a few.

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This is more efficient than the hot gas which provides the thrust in a conventional rocket.

ECONOMIST: A large asteroid sweeps by Earth. Where are the others?

Way back in November of 1985, on just its second mission, Atlantis experienced a blow-back of hot gases past the primary O-rings in one of its solid rocket boosters, resulting in serious erosion of said O-ring.

ENGADGET: Space Shuttle Atlantis ends its run of predicting disaster for other NASA shuttles

On a hot June evening at a ramshackle former gliderport 30 miles east of Dallas, John Carmack's rocket engine lit up with its blue flame spewing from the nozzle.

FORBES: Magazine Article