Engineers investigate another malfunction on SpaceX’s Falcon 9 rocket

Enlarge / The Merlin vacuum engine on SpaceX's Falcon 9 rocket fired for six minutes to place the Crew-9 mission into low-Earth orbit. (credit: NASA/SpaceX)

SpaceX is investigating a problem with the Falcon 9 rocket's upper stage that caused it to reenter the atmosphere and fall into the sea outside of its intended disposal area after a Saturday launch with a two-man crew heading to the International Space Station.

The upper stage malfunction apparently occurred after the Falcon 9 successfully deployed SpaceX's Crew Dragon spacecraft carrying NASA astronaut Nick Hague and Russian cosmonaut Aleksandr Gorbunov on SpaceX's Crew-9 mission. Hague and Gorbunov safely arrived at the space station Sunday to begin a five-month stay at the orbiting research complex.

The Falcon 9's second stage Merlin vacuum engine fired for more than six minutes to place the Crew Dragon spacecraft into orbit after liftoff from Cape Canaveral Space Force Station, Florida. The engine was supposed to reignite later to steer the upper stage on a trajectory back into Earth's atmosphere for disposal over the South Pacific Ocean, ensuring the rocket doesn't remain in orbit as a piece of space junk.