SpaceX Explosion Cause Still Unknown A Week Later

A week after a SpaceX rocket carrying a communications satellite to be used by Facebook exploded on its launch pad in Cape Canaveral, Florida, company officials are still trying to figure out what triggered the massive fireball that engulfed the Falcon 9 and resulted in a total loss of payload.

SpaceX CEO Elon Musk tweeted Friday morning that the explosion is "Turning out to be the most difficult and complex failure we have ever had in 14 years." Particularly, Musk said he is trying to figure out where a "quieter bang" before the explosion came from.

Video shot by USLaunchReport does contain a small noise before the explosion happens, but the video was shot from 2.5 miles away from the rocket. It's not quite clear what "quieter bang" Musk is referencing. The company is asking anyone with video, photos or audio of the explosion to send them to the company.

Watch: SpaceX Explosion at Cape Canaveral Destroys Facebook Satellite

Musk said the explosion happened "during a routine filling operation" when the engines were not running, and there was no apparent heat source.

It seems like Musk has some ideas, though.

One user tweeted at him and asked, "there are some videos on YouTube claiming something hit the rocket. Any reality there?" Musk replied: "We have not ruled that out."

Another user tweeted Musk and said the sound sounds "like a metal joint popping under stress. e.g. weld failing on strut, welded seam bursting, etc.” Musk told him, "Most likely true, but we can't yet find it on any vehicle sensors."

SpaceX was scheduled to help deliver the $200 million Amos-6 satellite into orbit on Saturday, Sept. 3. The satellite included capabilities that Facebook was going to use as part of its Internet.org project to bring internet access to remote parts of the world.

In October, Facebook and French satellite provider Eutelsat agreed to a 5-year, $95 million lease on some of Amos-6's broadband for Facebook's Internet.org project. Facebook partnered with Samsung, Ericsson, MediaTek, Nokia, Opera and Qualcomm to bring affordable internet access to underserved parts of the world.

SpaceX is the private spaceflight company run by Musk, the billionaire tech investor who also started PayPal and Tesla Motors.

Image via USLaunchReport, YouTube