Thermal Imagery Analysis of Continued Activity at Yongbyon

Nuclear Weapons
, by , , and LANDSAT 7 and LANDSAT 8 thermal infrared satellite imagery in January and February show that warm water is being discharged from the 5MWe reactor at Yongbyon, confirming that the reactor and its cooling system are in operation. Thermal patterns from the same period suggests that the IRT-DPRK reactor, the Radiochemistry Laboratory, and the centrifuge plant are occupied, but not necessarily operational, and not in a state of shutdown. 

Thermal Imagery Analysis of Yongbyon

Nuclear Weapons
, by , , and Recent thermal infrared imagery of the Yongbyon Nuclear Research Center show warm water being discharged from the cooling system of the 5MWe reactor and that the reactor is in operation. During the past several months, water discharge from the reactor and probable steam exhaust from the steam turbine and electric generator hall has been observed in visible satellite imagery. Through thermal imagery, it can be determined that the water that is being discharged is indeed warm water discharge from the reactor's cooling system.

Current Status of the Pyongsan Uranium Concentrate Plant (Nam-chon Chemical Complex) and January Industrial Mine

Nuclear Weapons
, by , and The Pyongsan Uranium Concentrate Plant remains the sole verified producer of uranium concentrate in North Korea. As such it represents the foundation upon which the nation’s production of fissile material for nuclear weapons is built. Commercial satellite imagery collected from April through October 2021 continues to demonstrate that despite the absence of any nuclear testing by North Korea since 2017 the Pyongsan Uranium Concentrate Plant remains operational, continues to be maintained, and is producing uranium concentrate (U3O8, “yellowcake”).

Thermal Imagery Indicates Activity at Yongbyon Nuclear Reprocessing Facilities

Nuclear Weapons
, by , , and Recently acquired LANDSAT 7 and 8 thermal infrared imagery of the Yongbyon Nuclear Research Center provide strong indications that during March and April 2021, activity involving the heating of buildings and operations of facility support systems had resumed at several locations. These indications reveal clear patterns, distinct from the surrounding terrain and daily solar heating patterns, that suggest that the Radiochemistry Laboratory, its associated thermal plant, and the centrifuge plant resumed operations during the early part of March 2021 and have continued into mid-April 2021.

Reprocessing Activity at Yongbyon’s Radiochemistry Laboratory?

Nuclear Weapons
, by and At the Yongyon Radiochemistry Laboratory, steam (or smoke) rising from any of the stacks within the radiochemistry laboratory itself is not often observed in commercial satellite imagery. However, the March 30 image shows a plume of steam or smoke emanating from a small support building in the center of the facility. This, while not an indicator of a reprocessing campaign itself, indicates that the building is occupied and being heated.

Recent Activity at the Pyongsan Uranium Concentrate Plant (Nam-chon Chemical Complex) and January Industrial Mine

Nuclear Weapons
, by , and Commercial satellite imagery collected during the past eight months indicates that despite the absence of any nuclear testing by North Korea since 2017, the Pyongsan Uranium Concentrate Plant remains operational, is producing uranium concentrate (U3O8, “yellowcake”), and continues to be updated. Yellowcake can be enriched to become highly enriched uranium (HEU), which can be used to produce nuclear weapons.

We Must Prevent North Korea from Testing Multiple Reentry Vehicles

Military, Nuclear Weapons
, by If unchecked, North Korea is increasingly likely to resume strategic weapons testing in the months ahead—including tests of the technologies necessary for its missiles to carry multiple nuclear-capable reentry vehicles (RVs). Such missiles would, at a minimum, increase Pyongyang’s ability to challenge U.S. missile defenses, to make the most of its limited resources for strategic weapons production, and to threaten U.S. targets more credibly despite its limited flight testing of RVs.