Redox metals such as Fe, Mo, V, Ni, Cu, and Mn have played a pivotal role in shaping Earth’s biogeochemical cycles and the evolution of life. Building on this concept, the DeepTrace project is developing a groundbreaking mechanistic, analytical, and predictive framework for the nanoparticle-fueled co-mobilization of these catalyst metals across Earth’s marine redox interfaces. By elucidating the formation, distribution, and detection of metal-bearing nanoparticles, DeepTrace aims to establish a novel basis for inferring metal catalysis in complex environmental systems. Extending this idea to the search for extraterrestrial life, the project builds on the notion that putative hydrothermal vents on the ocean floors of Ocean Worlds -such as Europa and Enceladus- trigger eruptions that eject water plumes through ice cracks. While most volatile or elemental species decay during this process, stable nanoparticle forms can survive and be detected in the plumes, providing critical clues about the underlying ocean chemistry. In order to seize this unique opportunity, the NASA Europa Clipper Mission, currently on its way to the Jupiter system, is equipped with time-of-flight mass spectrometers to detect the composition of these particle emissions. The ERC DeepTrace project is currently developing the detection mechanisms for oceanic nanoparticles that can be directly linked to the search of life-supporting habitats in the ocean worlds of the solar system.