The first stage of the Falcon 9 rocket lands successfully after its launch on Dec. 22, 2015. Credit: SpaceX Photos, CC0, via Wikimedia Commons
After a series of failed attempts and crashes, the launch of SpaceX’s Falcon 9 flight 20 on Dec. 22, 2015, was a success. In addition to lifting off and deploying 11 communications satellites into orbit, the rocket achieved a historic first when it returned to Earth in a controlled descent and landed upright.
During a six-month hiatus following the failure of the CRS-7 launch, the Falcon 9 had been upgraded for increased liftoff thrust and was the first to use a supercooled propellant of liquid oxygen and kerosene. In addition to being a success for SpaceX, the completed mission was a landmark in aerospace history, signalling an age in which single-unit rockets could be reused and space travel could be routine and affordable.
