The
HEALPix projection is a family of
map projections, the members of which are distinguished by their H and K parameters that describe the specific arrangement. The H=4, K=3 HEALPix projection, as shown here applied to
Earth, maps the sphere to twelve square facets (diamonds) on the plane, then divides these facets into pixels. This projection is widely used in
physical cosmology for maps of the
cosmic microwave background.
Map: Strebe, using Geocart