This is an approximation to the HEALPix base pixelization, consisting of 12 equal-area polygons.
Each polygon is specified by its four vertices, each of which consists of an azimuth and elevation, in degrees.

unit d

vertices 0 4
  0  90		           45   0		      0    48.189685104221	             90   48.189685104221
  0  90		           135  0		      90   48.189685104221	             180  48.189685104221
  0  90		           225  0                     180  48.189685104221                   270  48.189685104221
  0  90                    315  0                     270  48.189685104221		     0    48.189685104221
  0  48.189685104221       0    -48.189685104221      315  0				     45   0
 90  48.189685104221       90   -48.189685104221      45   0                                 135  0
180  48.189685104221       180  -48.189685104221      135  0                                 225  0
270  48.189685104221       270  -48.189685104221      225  0                                 315  0
 45  0                     0  -90                     0    -48.189685104221                  90   -48.189685104221
135  0                     0  -90                     90   -48.189685104221                  180  -48.189685104221
225  0                     0  -90                     180  -48.189685104221                  270  -48.189685104221
315  0                     0  -90                     270  -48.189685104221                  0    -48.189685104221