The incident, which involved the USS Connecticut, generated quite a bit of attention at the time, due – at least in part – to the intriguing lack of information regarding the identity of the object that the submarine had collided with.
According to reports, 11 crew members were injured, however fortunately nobody was seriously hurt.
Some speculated that the submarine had collided with an enemy vessel, while others maintained that the incident might have had something to do with the UAPs (unidentified aerial phenomena) that Navy pilots had previously pursued off the coast of the United States and which were rumored to be capable of operating both above and below the surface of the water.
Now though, according to the results of an investigation into the incident, what the submarine actually collided with was a previously uncharted seamount at the bottom of the South China Sea.
Essentially underwater mountains – these often huge structures can be found all over the world and are thought to be the remains of extinct underwater volcanoes.
They are targets for study by scientists due to their potential to host unique and varied wildlife.
They can also prove hazardous to vessels – as appears to have been the case here.
According to the NOAA, there are over 100,000 seamounts over 1km tall on the ocean floor, however scientists have so far only explored a tiny fraction of them – less than 0.1%.