Operation Deep Freeze is the U.S. Department of Defense’s annual joint, interagency mission that provides logistical, air and sealift support to the National Science Foundation (NSF) for the U.S. Antarctic Program (USAP); it enables transport of personnel, supplies, fuel, ice‑breaking and base support for scientific research in Antarctica.
Military Sealift Command (MSC) charters and operates civilian-crewed ships to move bulk cargo, vehicles and heavy equipment to Antarctic ports and McMurdo Station as part of sealift/logistics support for Operation Deep Freeze, working with the Joint Task Force–Support Forces Antarctica and NSF to deliver supplies and handle offload operations.
Typical resupply cargo for McMurdo includes food and consumables, research equipment and scientific instruments, building materials and heavy construction gear, vehicles and containers, bulk fuel, mail and spare parts needed to keep stations and field science projects operating through the Antarctic season.
Plantijngracht is a heavy-lift commercial cargo ship (a civilian, chartered heavy-lift vessel) contracted by MSC for the resupply mission; details such as owner/operator and flag are typically listed in maritime registries but the article identifies it as the chartered heavy‑lift ship conducting offload at McMurdo.
Resupply missions under the Operation Deep Freeze framework are conducted annually during the austral summer (roughly October–February), with a concentrated sealift and airlift season each year to serve the U.S. Antarctic Program.
McMurdo Station is located on the southern tip of Ross Island on the shore of McMurdo Sound, Antarctica; it is operated by the U.S. National Science Foundation (through the U.S. Antarctic Program) and hosts U.S. military and international partner personnel and contractors who support scientific research.