Now the company has begun testing this rocket as it prepares to meet its goal of relaunching a 'reusable' rocket by October.
On Thursday, July 28, SpaceX engineers successful conducted a full duration engine test firing of a recovered Falcon 9 first stage booster on a test stand at the company’s rocket development test facility in McGregor, Texas.
The used 15 story Falcon booster had successfully carried out an intact soft landing on an ocean going platform after launching a Japanese commercial telecommunications satellite only two months ago on May 6 of this year.
SpaceX has managed to land four rockets from space back on Earth, one on land and three on sea, with the latest successful sea landing on 28 May.
Mr Musk plans to relaunch the second rocket it successfully landed within the next few months.
If it goes ahead, this would make it the first relaunch of the private space company's rockets.
This move would take the firm, and the aerospace industry as a whole, another step closer towards reusable rockets becoming commonplace.
This could make deep space travel cheaper, helping pave the way for a viable manned mission to Mars.
Elon Musk’s goal is to radically slash the cost of launching rockets and access to space via rocket reuse in a way that will one day lead to his vision of a ‘City on Mars.’
The company plans to start offering a service to send payloads to Mars as early as 2018, with prices starting at 62 million $ for the Falcon 9 rocket.