Janis Niedra (RPT/Thermal Energy Conversion Branch) is using a Helmholtz coil to measure the approximate remanence of a magnet segment. The magnet segment being measured is similar to the ones used in the linear alternator of the Advanced Stirling Convertor (ASC) which was designed and built by Sunpower, Inc. The magnet (not shown in this view) is positioned in the slot cut along the top of the aluminum block which is positioned at the center of the coil in the region of uniform sensitivity. The ASC is the type of free-piston Stirling convertor that is used in the Advanced Stirling Radioisotope Generator (ASRG) currently being developed by Lockheed-Martin for the Department of Energy and NASA. GRC-2011-C-05116