Australian scientists have used a Lego pirate floating in a fish tank to show for the first time that enormous waves can appear from nowhere and engulf ships.
Sailors have long described massive waves that can appear in otherwise calm waters, causing danger, and even sinking ships - but these stories have until lately been taken with a pinch of salt.
Only recently has a prototype of how a rogue wave could develop – called the Peregrine soliton – been observed experimentally in fibre optics.
However, using a fish tank, a wave generator and a Lego pirate on a model ship, the team's shown that rogue waves much bigger than previously thought can occur - up to five times bigger than the other waves around them.
"This observation could have far-reaching consequences for our efforts to understand these waves that are, by far, still mysterious," says Australia National University's Nail Akhmediev.
He says that the large amplification of the rogue wave peak above the normal waves around it suggests the existence of a new class of waves – dubbed 'super rogue waves' - that develop due to the nonlinear dynamics of the surface elevation.
This is an extraordinary fact that could explain some mysterious observations of rogue waves in calm sea states," he says.
"Of course, in real oceans the problem will require more careful analysis, but we expect the result to have a significant impact on the studies of extreme ocean waves and more generally, extreme events in nature and society."
The Lego pirate survived unharmed. Phew.