Abstract: A detector for detecting optically undetectable sub-cm orbital debris. A ring detector comprising a current pulse transformer (CPT) in which a conducting wire coil is wrapped around a loop of high permeability material having a magnetic nanoparticle (MNP) core. Debris objects in low earth orbit become charged as they pass through local plasma. As each charged debris object passes through the coil-wrapped loop, its current generates an induced voltage pulse, which can be used to detect the presence of the debris object. By fielding such a detector on a satellite, a long duration survey of the debris distribution in the LEO region can be made as the satellite's altitude is systematically varied.