Magnetic and orbital ordering in the manganese based perovskites has been of huge interest in solid-state physics since the 1950's. More recently, the family of AA′3Mn4O12 quadruple perovskites have been realised, and are now known to support intricate ordering phenomena. In particular NaMn7O12 develops commensurate magnetic and orbital order, as in the well-known compound La0.5Ca0.5MnO3, whereas CaMn7O12 exhibits a more exotic incommensurate magneto-orbital helix. We have grown for the first time the Na0.5Ca0.5Mn7O12 solid solution, and a neutron powder diffraction experiment at WISH is essential to determine the magnetic structure in the three, low temperature magnetically ordered phases of this new material, which may be found to bridge the gap between exotic magneto-orbital helices and the well established collinear, commensurate order.