By Rob Mclean @CNNMoney December 22, 2015: 11:45 AM ET
Blast off
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SpaceX's Falcon 9 rocket lifts off Dec. 21. The primary mission was to put 11 small satellites into low orbit for Orbcomm's (ORBC) new satellite network.
But SpaceX was also attempting something audacious: Its plan called for the booster stage rockets to return to earth, and gently settle onto a landing pad.
