What SpaceX's Falcon Heavy launch means for the future of spaceflight

SpaceX had a pretty big day on Tuesday. 
The Elon Musk-founded company successfully launched its maiden flight of the huge Falcon Heavy rocket and landed two of its three main boosters back on Earth after sending a Tesla Roadster to space. 
With this launch, SpaceX and Musk effectively made a long-shot rocket dream come true before our eyes and made good on a promise made more than five years ago.
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