The December 2010 flight, much shorter and less demanding than this weekend's effort, wasn't without problems: the rocket experienced some engine hiccups on ascent.

WSJ: SpaceX's Pioneering Flight Plans

The amount of radiation likely won't change unless there's a rocket engine developed that can speed up the interplanetary ride, researchers said.

NPR: Astronauts Face Radiation Threat On Long Mars Trip

The sports car look of the cabin is almost entirely achieved by the seats, but that feel is so reinforced by the firmer ride, the rasp of the exhaust and the quick reflexes of the engine and suspension that you can't help but think you're really in a posh rocket sled.

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