Falcon 9 launch from Florida with the Dragon spacecraft (Credit: SpaceX)

Falcon 9 launch from Florida with the Dragon spacecraft (Credit: SpaceX)

The SpaceX Dragon spacecraft is on course to pass 2.4 km underneath the International Space Station. This fly-under is part of a series of manoeuvres and tests as the spacecraft approaches the ISS ahead of the scheduled docking tomorrow. The Dragon is set to pass directly underneath the ISS at around 13:30 CEST (11:26 UT).

Launched from Florida on Tuesday, the Dragon spacecraft is carrying food and supplies for the Station crew. It is the first time a privately built spacecraft has been launched to the ISS.

Dragon berthing is scheduled for Friday

Dragon berthing is scheduled for Friday

During the fly-under the ISS crew will send a test command to the Dragon spacecraft and receive a response, this is to make sure that they can communicate with each other in case other commands such as hold, retreat, or even abort, are needed during the rendezvous operations. The Dragon’s relative GPS navigation will also be tested during the fly-under – this enables the spacecraft to navigate according to the position of the ISS and will be essential during tomorrow’s complex approach.

Once the fly-under is finished Station managers will meet to review the performance of the spacecraft and give the go-ahead for tomorrow’s rendezvous and berthing.

Dragon is scheduled to rendezvous with the ISS on Friday 25 May, when Expedition 31 crewmembers André Kuipers and Don Pettit will use the Station’s robotic arm Canadarm2 to grapple the spacecraft and manoeuvre it into position to mate with the Harmony module’s Earth-facing docking port.