Elon Musk, CEO of SpaceX, tweeted that the company's Falcon 9 explosion on Thursday occurred as the rocket was being filled with propellant.
Falcon 9 uses liquid oxygen and rocket-grade kerosene propellant to launch it into space. Once the propellant ignites, the rocket shoots off the launchpad with 1.7 million pounds of thrust.
The explosion occurred during a routine static test-fire ahead of Saturday's planned (and now scrubbed) launch of Facebook's first satellite. The test fires the rocket's engines without actually launching it into the air.
Musk said the explosion "originated around [the] upper stage oxygen tank," which is made of aluminum-lithium alloy.
Loss of Falcon vehicle today during propellant fill operation. Originated around upper stage oxygen tank. Cause still unknown. More soon.
— Elon Musk (@elonmusk) September 1, 2016SpaceX also retweeted Musk's explanation, and added some information:
Update on this morning's anomaly pic.twitter.com/1ogCMPCY44
— SpaceX (@SpaceX) September 1, 2016Thankfully, no people were near the rocket while the propellant was being loaded, so there were no injuries from the blast. The satellite the rocket was carrying was destroyed.
The explosion was huge, though. Florida residents reported sliding glass doors coming off their hinges, and some thought their house had been hit by lightning, according to local Orlando news outlets.
WFTV said on air: "This may have been the biggest explosion we have ever felt in central Florida."
SpaceX and Musk both said they don't know the root cause of the explosion yet and are still investigating.
The loss will likely throw a wrench in the private space company's ambitious launch plans for the rest of the year.
SEE ALSO: A rocket SpaceX was testing exploded on a launch pad in Florida
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