Read more: Click here to read the original, longer version of this story
BUBBLES have never been so deadly. The South Korean military ship, Cheonan, which sank in March killing 46 people, was hit by a 鈥渂ubble jet鈥� from a North Korean torpedo, a report by a team from South Korea, Australia, the US, the UK and Sweden has concluded.
The report, released last week, says that the extensive damage to the ship 鈥� it had been split in half 鈥� is characteristic of the shock wave and powerful water jet produced when a torpedo explodes. Fragments of a type of torpedo known to be used by North Korea were found near the wreck.
Advertisement
Contrary to popular belief, modern torpedoes don鈥檛 explode on impact with a ship. Instead, they detonate a few metres off the hull, says Geoffrey Forden of the Massachusetts Institute of Technology. The explosion releases hot gases, which form a very high-pressure bubble in the water. The bubble鈥檚 rapid expansion and contraction churns the water, damaging the ship鈥檚 hull. When the bubble touches the ship, it depressurises rapidly as gas rushes along the hull towards the water鈥檚 surface. Water rushes in to fill the gap, forming a jet powerful enough to rip the ship in two.
The South Korean government has asked the United Nations for punitive measures against its neighbour; North Korea says the report is 鈥渟heer fabrication鈥� and that any attempt at retaliation will be met with all-out war.
鈥淣orth Korea claims the report is a 鈥榮heer fabrication鈥� and retaliation will be met with all-out war鈥�