The Death Star project concept falls in a practical sense at the first hurdle as nobody knows how to build a near light speed propulsion engine for it.

FORBES: White House Denies Petition Request To Build A Death Star

While the ship will not travel at warp speed, with an ion propulsion engine powered by a 1.5GW nuclear reactor, it can travel at a constant acceleration so that the ship can easily get to key points of interest in our solar system.

MSN: Spaceship Enterprise in 20 years? Beam me up!

Conventional hybrids use mainly the gasoline engine for propulsion, drawing on the electric drive and batteries only occasionally to (impressively) improve gasoline efficiency.

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