The military applications for the proposed magnetic cooler include cooling systems on space-based surveillance, missile detection, and missile tracking systems. Scientific applications include cooling systems for material microanalysis using X-ray microcalorimeter spectrometers, cryogenic particle detectors, and biomolecule mass spectrometry using superconducting tunnel junction detectors. The proposed AMRR system will enable NASA to carry out future science missions that use cryogenic infrared, gamma ray, and X-ray detectors. Potential missions include the International X-ray Observatory (IOX) and the Single Aperture Far-Infrared observatory (SAFIR). These detectors need to operate at temperatures in the range of 4 K to below 1 K to reduce the thermal emission of the detectors themselves and to achieve high sensitivity and resolution. The vibration-free, lightweight AMRR can provide efficient cooling for these missions at the required temperature ranges. The fabrication technologies developed for the magnetic regenerator can also be applied to the fabrication of advanced regenerators for mechanical cryocoolers.