Another resupply mission to the International Space Station (ISS) ended in failure today as SpaceX's CRS-7 mission exploded in midair shortly after liftoff. The unmanned Dragon cargo ship atop a Falcon 9 rocket launched from Launch Complex 40 at Cape Canaveral Air Force Station at 10:21 am EDT. SpaceX launch control indicated no problems prior to launch and weather was good, but approximately 2 min 18 sec into the flight, the Falcon 9 experienced an anomaly and broke up over the Atlantic Ocean.

The cause of the incident is still under investigation, with range safety officers evaluating available data according to a statement from the US Air Force 45th Space Wing.

SpaceX founder and CEO Elon Musk tweeted that telemetry indicated overpressure in an upper stage oxygen tank, but did not indicate that this was related to the failure.

The unmanned SpaceX cargo ship was carrying over 4,000 lb (1,814 kg) of supplies to the ISS, including materials for numerous scientific experiments and adapter modules for docking the next generation of spacecraft with the station.

Though not a cause for immediate concern, the loss of this cargo is worrying because it is the third resupply mission to the ISS to fail in less than a year, following the previous Antares launch vehicle explosion and the failure of the Russian Progress 59 cargo ship to respond to commands after lift off. CRS-7 was expected to make up for some of these losses, but today's events once again raise the question of the station's future, which could see it operating with a reduced crew or, in a worst case scenario, abandoned altogether.

The next resupply mission is the Progress 60P mission scheduled to liftoff on July 3 from the Baikonur Cosmodrome.

The video below is from SpaceX's live feed of the launch.

View gallery - 4 images