a circular segment 2 supported on hinges 3 and 4 aligned on the polar axis of an equatorial mount 5 mounted on a leveling base 6 the circular segment 2 has a holding means 7 for positioning it on a time dial 8 the solar ray directed assembly has shoes 9 and 10 bearing at spaced apart points on the circular segment rim 11 a declination indicator 12 a replica of the sun 13 a target member 14 a declination holding means 15 outer rim spacer 16 inner rim spacers 17 and straddle parts 18 and 19 shoes 9 and 10 declination indicator 12 and outer rim spacer 16 may be combined in a single piece of flat stock straddle parts 18 and 19 may be similar outer rim spacer 16 and inner rim spacers 17 may have the same thickness as the circular segment 2 or other means not shown such as springs or a pressure pad may be used for maintaining parallel alignment of the straddle part 18 or 19 with the circular segment 2 the declination holding means 15 may be a simple leaf spring as shown other means not shown such as a screw clamp may be used to hold shoes 9 and 10 in contact with the circular segment rim 11 and retain the declination setting the target 20 on the target member 14 and the aperture 21 on the replica of the sun 13 are on a line of sight which is parallel to a radial line originating at the intersection of the polar axis with the equatorial plane and parallel to the face plane of the circular segment 2 an aperture 21a and a corresponding target 20a may be located on the opposite side of the circular segment 2 as.