— NASA (@NASA) June 28, 2015
The accident was the third in less than a year involving US and Russian supply ships bound for the International Space Station, and raised new concerns about the flow of food and gear to the astronauts living in orbit.
Skies were sunny and clear for the 10:21 am (1421 GMT) launch of the gleaming white Falcon 9 rocket that was meant to propel the Dragon cargo ship on a routine supply mission, the seventh for SpaceX so far.
But two minutes, 19 seconds into the flight, contact was lost. Live television images from SpaceX’s webcast and NASA television showed a huge puff of smoke billowing outward for several seconds, and then tiny bits of the rocket falling like confetti against a backdrop of blue sky.
“The vehicle has broken up,” said NASA commentator George Diller.
SpaceX’s live webcast of the launch went silent as the rocket exploded. Moments later, a SpaceX commentator said “there was some kind of anomaly,” and noted that the rocket had ignited its nine Merlin engines and reached supersonic speed.
Later, on Twitter, Musk said the Falcon 9 “experienced a problem shortly before first stage shutdown,” referring to the phase of flight before the cargo ship would have been able to separate from the first stage of the rocket and reach orbit.
Falcon 9 experienced a problem shortly before first stage shutdown. Will provide more info as soon as we review the data. — Elon Musk (@elonmusk) June 28, 2015
The problem appeared to be linked to excessive pressure in the liquid oxygen tank, wrote Musk, a lifelong space enthusiast who also heads Tesla Motors.
There was an overpressure event in the upper stage liquid oxygen tank. Data suggests counterintuitive cause.
— Elon Musk (@elonmusk) June 28, 2015
An investigation into the cause is ongoing.