Three weeks ago, a Russian and American crew was streaking towards the International Space Station in a Russian-built Soyuz rocket from Kazakhstan. It would’ve normally barely been a blip on the news. The Soyuz is widely known to be extremely reliable. But something went wrong, and the . This is the moment everything went wrong from the outside.

As you can see in this Twitter video, whole launch proceeds normally, up until about the 1:26 mark. Instead of seeing the famous as the rockets fall away, there’s a huge shunt and debris flying everywhere as the rocket tumbles erratically:

Russian officials are still trying to determine precisely what went wrong, but their best guess so far is a sensor that was damaged during assembly of the rocket, according to the :

A Russian Soyuz rocket capsule was forced to make an emergency landing shortly after launch last month because of a faulty sensor, investigators say.

Russian officials believe the component was damaged during assembly.

They warned that two other Soyuz rockets could be defective, and said additional checks have been introduced.

The faulty sensor somehow caused one of the four strap-on booster rockets to fail to fall away smoothly from the core of the launch vehicle, and instead may have smashed against it.

The crew, composed of American astronaut Nick Hague and Russian cosmonaut Alexey Ovchinin, was able to make a safe landing on the Kazakh steppe after enduring high G forces due to the unusual descent. As our friends at reported a few weeks ago:

Hague, 43, is now back in Houston, and he recently to the Associated Press about the ordeal, saying he knew he needed to stay calm despite all hell breaking loose. With lights flashing and alarms blaring, he and Ovchinin were tossed from side to side and pushed back into their seats during the separation failure.

“Any time you’re launching yourself into space and your booster has a problem when you’re going 1,800 meters per second, things are pretty dynamic and they happen very fast,” he said.

The Soyuz module then flung away violently from the rocket core. For a brief moment, the crew experienced zero gravity. Hague said he even saw the blackness of space and the curvature of the Earth.

The exact instant when things went wrong could be seen from inside the Soyuz capsule on the NASA livestream, as Hague and Ovechnin were shaken like maracas right as the problem started:

But seeing it from the outside, with the backdrop of the Earth and the black sky as a frame of reference, makes it look so much worse.