U.S. Antarctic Mission Proceeds as Polar Star Departs Australia

The U.S.’s annual supply mission to Antarctica known as Operation Deep Freeze is moving into its next phase as the Polar Star, the U.S. Coast Guard’s only heavy icebreaker, started the final leg of its deployment. It will take her from Australia to the bases in the Antarctic. It marks the icebreaker’s 28th voyage to Antarctica.

Operation Deep Freeze is a joint military service mission to resupply the United States Antarctic stations of the National Science Foundation, which is the lead agency for the United States Antarctic program. The Polar Star provides heavy icebreaking capabilities to facilitate sealift, seaport access, bulk fuel supply, and cargo handling for two of the U.S.’s three research stations in Antarctica, including McMurdo Station which is the largest. The cutter’s icebreaking capabilities enable the delivery of critical supplies to sustain the year-round operations and support international partnership in the harsh Antarctic environment.

Operation Deep Freeze is one of the more challenging U.S. military peacetime missions due to the harsh environment in which it is conducted. Antarctica is the coldest, windiest, most inhospitable continent on the planet, and the USCG highlights that each trip requires careful planning and coordination. During the transit, the crew received training and prepared to support the vital mission despite the austere environment. 

The Polar Star started this year’s deployment by departing from its homeport of Seattle on November 22. It has traveled approximately 7,000 miles with a stop in Honolulu, Hawaii, before reaching Sydney, Australia on December 21.  The icebreaker hosts tours and outreach while in Australia while also loading fuel and supplies. She departed on December 27 for the trip across the Southern Ocean to reach Antarctica.

"Polar Star is unique in its ability to operate in the dynamic polar regions and we are looking forward to joining our service partners operating there," said Lt. Cmdr. Rachel Rand, Polar Star’s operations officer.  

She is outfitted with six diesel and three gas turbine engines that produce up to 75,000 horsepower. The USCG highlights she is their most powerful vessel with capabilities to continuously break six feet of ice at 3 knots and ram through ice she can encounter in Antarctica at up to 21 feet thick. The USCG has been working to extend her service while the replacement icebreakers are delayed. In December, approval was finally given to begin construction on Polar Sentinel, the first next-generation icebreaker, but she is not expected till 2029.

The first phase of this year’s Operation Deep Freeze began in October 2024 when a team of Seabees departed to undertake a waterfront construction project in Antarctica. It is the first time since 1994 that Seabees were officially involved in operations on Antarctica.

The current “ice pier” at McMurdo Station the USC reports became unreliable to sustain essential logistics operations. The Seabees were sent to construct infrastructure that supports the installation of a new loading/offload infrastructure project at McMurdo Station. The new project will provide an enduring engineering solution to facilitate the safe and efficient loading and offloading of supplies to McMurdo.

In addition to the Polar Star, the U.S. sends a mission traditionally with two merchant ships that depart around the end of the year. In that phase of Operation Deep Freeze, vital supplies are transported to the stations, and material is loaded for return to the United States.