Signal in the Shadows: Digitally Reconstructing the Yu Son

In November 2025, OSC published an investigation into the networks used to facilitate the movement of Russian oil into North Korea in violation of UN Security Council sanctions. As part of that work, we focused on the Yu Son (IMO 8691702), a DPRK-owned vessel and one of North Korea's most active oil tankers.

Early in the investigation, we found ourselves asking a deceptively simple question: how can you tell how deep a vessel is sitting in the water from satellite imagery alone?

In this piece, we walk through our Digital Twin Reconstruction (DTR) methodology to answer that question with greater precision and confidence. By combining geospatial analysis with techniques drawn from 3D modelling and visual effects, the process allows us to reconstruct and investigate vessels even in information-scarce environments.

The result is both a new analytical workflow and a different way of engaging with geospatial intelligence: one that helps us test what can be measured, reconstructed and understood from limited source material.

View the Gaussian splat interactive model: https://yuson-model.opensourcecentre.org