On Thursday, SpaceX took another step toward reusing rockets when it fired the nine engines on the first stage of a Falcon 9 booster it launched in May. The company released video of the full-duration engine firing, which mimicked the length of a first-stage burn toward orbit, conducted at its test site in MacGregor, Texas.

This particular booster, which launched a Japanese communications satellite to geostationary transfer orbit on May 6, will not be re-flown. According to Spaceflight Now, the company designated it as a reference vehicle because it weathered extreme temperatures during its reentry into Earth's atmosphere. The rocket will undergo additional tests as engineers determine the readiness of flown boosters for additional flights into space.

This test plan is part of SpaceX's plans to re-fly the first booster it landed at sea, the rocket it used in April to launch a cargo delivery mission to the International Space Station. That first stage had an easier ride back to the surface because it boosted a payload into low-Earth orbit, rather than the much higher geostationary altitudes common for communications and spy satellites.

It is not clear when the first reuse flight will occur, although SpaceX chief executive Elon Musk has said it will happen this year. During an American Institute of Aeronautics and Astronautics propulsion meeting this week, former US Air Force official Gary Payton said he believed SpaceX had found a customer for the first re-launch of an orbital rocket. "I understand, as a of a few days ago, that they have found a user for that first, previously flown first stage," he said. "So that is part of the market test."

Reusability has long been a goal of the aerospace community. But despite earlier progress by NASA and some of its contractors, only now are SpaceX and Blue Origin beginning to deliver on the promise of rapid and inexpensive turnaround of rockets flown into space. Re-launching a rocket for a paying customer would validate the idea of reusability as well as its commercial viability.

Listing image by SpaceX