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The Polar Star at the pier in Seattle, WA.
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The Expedition - The Ship
Overview | Objectives | Science Crew | The Ship

The Coast Guard Cutter Polar Star is the world’s most powerful non-nuclear icebreaker and operates from their home port at Pier 36, Seattle, Washington.

Polar Star’s primary missions are scientific support in the Arctic and Antarctic, ice escort of shipping, and logistics support for U.S. Government interests in both polar regions. In addition to providing support to polar stations, Polar Star is equipped to function as a major scientific platform for oceanographic fieldwork. It has laboratories, offices, and sleeping quarters to support 20 scientists and technicians. Polar Star, like all Coast Guard cutters, is also prepared to perform search and rescue, law enforcement, and environmental response missions.

Polar Star is commanded by Captain David W. Mackenzie. A typical crew complement is 20 officers and 140 enlisted personnel. The crew is assigned to different departments, such as the operations department and the engineering department. The departments work together as a team to make sure the ship completes its missions efficiently and safely.

Icebreaking capabilities
Although Polar Star is capable of breaking very thick ice, rule number one in ice breaking is, “if possible, avoid the ice.” This is simply because it takes longer, consumes more fuel, and produces more wear and tear on the ship when battering through the ice. However, when there is ice between the ship and its destination, Polar Star can do the job. The most efficient way to break through ice is to find the weakest points in the ice, such as existing cracks or open areas called “leads.” When there are none, the ship will look for “first year ice”, which is often flat and 2-6 feet thick. As sea ice gets older it becomes considerably stronger, and changes color to a distinctive deep blue. Polar Star can maintain a continuous speed of 3-5 knots through most first year ice. When the ice stops Polar Star, the cutter will back up approximately one to two ship lengths (200-800 feet) then steam ahead with as much momentum as possible. The momentum of the ship will carry the cutter up higher on the ice, and push it ahead with more force to break through the ice.

Polar Star has sufficient hull strength to absorb high-powered rams into the ice. The hull shape of the Polar Star is designed to maximize icebreaking by efficiently combining the forces of the ship’s forward motion, the downward pull of gravity on the bow, and the upward push on the stern due to its inherent buoyancy. Polar Star has other unique features designed for Polar Operations. Fuel tanks can carry over 1.3 million gallons of fuel to provide Polar Star with 60-150 days of endurance. A central hydraulic system operates cranes, boat hoists, and the anchor system. Polar Star also carries two H-65 helicopters to carry out scientific support, ice reconnaissance, cargo transfer, and search and rescue.

The ship has five laboratories and berthing space to accommodate up to 20 scientists. The oceanographic winches and lab spaces give scientists the ability to conduct at-sea studies in geology, oceanography, sea-ice physics, and other scientific disciplines.