The crew of the Coast Guard’s medium icebreaker Healy was back in Seattle Thursday following four months of Arctic operations.

The crew conducted two separate missions that included operations in the Bering Sea, Chukchi Sea and Arctic Ocean. Healy’s Sept. 5 arrival at the North Pole marked the first time a U.S. surface vessel has reached 90°N unaccompanied.

The crew departed Dutch Harbor, Alaska, Aug. 9 for Geotraces, an international effort to study the distribution of trace elements in the world’s oceans to establish the effects of these elements on global climate change.

Healy was commissioned in 1999 and is the newest and largest U.S. high latitude icebreaker, boasting extensive scientific capabilities. The cutter is based out of Seattle with a permanent crew of 87. The cutter’s primary mission is scientific support, but she is also capable of conducting search and rescue, ship escort, environmental protection, and the enforcement of laws and treaties in the Polar Regions.