"It's the design of the hull that is quite helpful, it looks like a bathtub," said Capt. Jason Hamilton, a former officer both on the Polar Star and its sister ship the Polar Sea, and now a legal officer for the Coast Guard, based in Seattle. "It rides up on top of the ice and breaks it."
There are other ways to break ice. The Swedish icebreaker Oden, which the U.S. National Science Foundation (NSF) leased for several years while the Polar Star was being refitted, uses hydraulic pumps to lift its square-shaped bow on top of the ice in an up-and-down crushing motion.
The Polar Star left Australia and is expected to arrive near the Chinese and Russian vessels this weekend. By then, the captain will have a better idea of what he’s up against. Danger is everywhere; uncharted currents move ice packs quickly and navigators having difficulty telling how thick the ice is at any given time.
Satellite data and surface ridges that indicate where packs are colliding on the surface only give an estimate. Hamilton says the Polar Star will need to leave itself an escape route.
"You break the ice in a manner so you can back out and don't put your situation where you are in extremis," he said.
For those waiting for rescue, time is spent fighting boredom and hoping that enough pressure will ease so the ice floes will move.
"You get a little anxious because you can't do much science," said Till Wagner, an ice scientist and postdoctoral fellow at the Scripps Institute of Oceanography in La Jolla, Ca., who has been icebound on research cruises in both the Arctic Sea and Antarctic Ocean.
"Once you are stuck in the ice, you just have to wait. In a way it is magical. You are in this vast space and it's quiet. Nothing happens. There is a certain tranquility about it."
So what if the American icebreaker gets stuck? There may be one final rescue squad. The Russian nuclear-powered icebreaker Let Pobedy can ram through 10-foot ice and packs a 74,000-horsepower wallop. However, its last known position was near its home port of Murmansk, Russia, on the other side of the planet.