Japanese shipping company Mitsui OSK Lines (MOL) has entered into an agreement to operate Mirai II, Japan’s first icebreaking Arctic research vessel, for the Japan Agency for Marine-Earth Science and Technology (JAMSTEC).
The 13,000GT ship is due for delivery on December 18, 2026, at Japan Marine United’s Isogo plant in Yokohama, ahead of her first Arctic expedition in the summer of 2027.
The agreement covers vessel operation and related services. MOL expects operations to begin in December, while JAMSTEC will remain the ship’s owner.
Upon completion, the vessel will have a length of 128 metres, a beam of 23 metres, and accommodation for 97 people. She was designed to be capable of breaking through flat first-year ice up to 1.2 metres thick continuously at three knots.
The vessel’s Polar Class 4 designation will allow year-round navigation in thick first-year ice that may contain old ice.
MOL was selected as the vessel’s prospective operator in 2023 and tasked with dispatching crew before commissioning. Those personnel were to work at the shipyard during outfitting, checking the vessel against construction specifications and identifying defects before serving aboard after delivery.
Construction of Mirai II began in August 2021, and the naming and launch ceremony took place in March 2025. Outfitting and installation of observation equipment continued after launch. Sea trials and other tests have been under way since June of this year.
MOL said it would draw on the, “operational experience it has accumulated on the Northern Sea Route,” and its expertise in handling LNG fuel.
The ship’s power generation equipment will include three diesel generators rated 5,600 kW each and one dual-fuel diesel generator rated 2,600 kW.
Mirai II will be equipped for atmospheric, meteorological, oceanic and biological observations, as well as deployments of remotely operated and autonomous underwater vehicles. The vessel’s equipment will also support seafloor sonar surveys, sediment sampling, and observations beneath sea ice.
JAMSTEC’s previous research vessel, Mirai, was retired in December 2025 after 28 years of service. She had ice-resistant characteristics but could not break into sea-ice areas.
The new ship’s icebreaking target and planned dual-fuel power system were included in the project’s early design plans.
