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nametext
HTMThe Hierarchical Triangular Mesh (HTM) is a partitioning scheme to divide the surface of the unit sphere into spherical triangles. It is a hierarchical scheme and the subdivisions have not exactly, but roughly equal areas. HTM is used to index the coordinates in the object databases for faster querying speeds. For more details, and downloadable software, see the HTM Website at http://www.sdss.jhu.edu/htm/.