The Coast Guard says the icebreaker Polar Star is returning to Seattle Friday after a 108-day deployment to help resupply McMurdo Station, Antarctica.
The vessel broke a 12-mile lane of ice up to 10-feet thick, clearing the way for a tanker and cargo ship.
In January, the Polar Star also was dispatched to help two vessels stuck in sea ice, but they broke free on their own.
The 399-foot Polar Star has a crew of 140. The 38-year-old-ship underwent an overhaul that allowed a U.S. icebreaker to support the Antarctic resupply effort for the first time in six years.