The design can, in theory, produce very high specific impulses while still being well within the abilities of current technologies.

This provided 10% higher thrust, and higher specific impulse as well.

It is also often used for upper-stage motors, due to its high specific impulse.

For example: salt can be added to increase the density of the reaction mass resulting in a higher specific impulse.

Physically, even at high nuclear impulse, they were well more than a year away.

Liquid oxygen is useful in this role because it creates a high specific impulse.

A propulsion method with a higher specific impulse is more propellant-efficient.

A high specific impulse means that a rocket needs less fuel to perform as well.

An engine with a higher specific impulse uses fuel better.

Negative, sir; they're in open space, moving at high impulse.