There's now video of the SpaceX Falcon 9 explosion in Cape Canaveral, Florida, on Thursday morning.
The organization US Launch Report captured the incredible footage of the incident. You can see the explosion at 1:10:
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The explosion occurred during a routine static test fire ahead of Saturday's planned (and now scrubbed) launch of Facebook's first satellite. A static test fire activates the rocket's engines without actually launching it into the air.
SpaceX and its CEO Elon Musk said the explosion occurred as they were filling the rocket with propellant and "originated around the upper stage oxygen tank," which is made of aluminum-lithium alloy.
https://twitter.com/mims/statuses/771395212304277504
Update on this morning's anomaly pic.twitter.com/1ogCMPCY44
Thankfully, 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.
SpaceX and Musk both said they don't know the root cause of the explosion yet and are still investigating.