Vid A SpaceX video posted late last week is as boring as it gets: the Falcon 9 rocket doesn't even lift off.

It is, however, special for this: it's the first time a rocket's first stage has been fuelled up and fired* after it's been to space.

Youtube Video

The nine Merlin engines were dosed up with kerosene and given their full burn time, as part of the Elon Musk company's preparation for a future launch that will be the first time in history a booster will lift a second cargo.

Thursday's test firing was the booster that launched a Japanese communications satellite in May. It's had something of a hard life, which is why it was used for the test firing: to get the satellite into geostationary orbit demanded a high-velocity launch.

Spaceflight Now notes the JCSAT 2B launch exposed this booster to a 6,300 km/h re-entry before it successfully dropped on its barge in the Atlantic Ocean.

For a payload flight, SpaceX plans to use the booster that hoisted an ISS resupply in April. When that rocket landed, Elon Musk bullishly predicted the booster would make its return to space by June. ®

* David Wilkins wrote in to make the distinction that: "This is not the first time a recovered booster has been fired, the first was performed at Pad 39A back in January. This however is the first full duration burn by a recovered stage, and part of the normal checkout of engines, as SpaceX fires each Merlin at McGregor before their return to Hawthorne for final assembly."