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Table 23

Reserved celestial coordinate algorithm codes.

Code φ 0 θ 0 Properties1 Projection name

Zenithal (azimuthal) projections
AZP 90° Sect. 5.1.1 Zenithal perspective
SZP 90° Sect. 5.1.2 Slant zenithal perspective
TAN 90° Sect. 5.1.3 Gnomonic
STG 90° Sect. 5.1.4 Stereographic
SIN 90° Sect. 5.1.5 Slant orthographic
ARC 90° Sect. 5.1.6 Zenithal equidistant
ZPN 90° Sect. 5.1.7 Zenithal polynomial
ZEA 90° Sect. 5.1.8 Zenithal equal-area
AIR 90° Sect. 5.1.9 Airy

Cylindrical projections
CYP Sect. 5.2.1. Cylindrical perspective
CEA Sect. 5.2.2 Cylindrical equal area
CAR Sect. 5.2.3 Plate carrée
MER Sect. 5.2.4 Mercator

Pseudo-cylindrical and related projections
SFL Sect. 5.3.1 Samson-Flamsteed
PAR Sect. 5.3.2 Parabolic
MOL Sect. 5.3.3 Mollweide
AIT Sect. 5.3.4 Hammer-Aitoff

Conic projections
COP θ a Sect. 5.4.1 Conic perspective
COE θ a Sect. 5.4.2 Conic equal-area
COD θ a Sect. 5.4.3 Conic equidistant
COO θ a Sect. 5.4.4 Conic orthomorphic

Polyconic and pseudoconic projections
BON Sect. 5.5.1 Bonne’s equal area
PCO Sect. 5.5.2 Polyconic

Quad-cube projections
TSC Sect. 5.6.1 Tangential spherical cube
CSC Sect. 5.6.2 COBE quadrilateralized spherical cube
QSC Sect. 5.6.3 Quadrilateralized spherical cube

HEALPix grid projection
HPX Sect. 62 HEALPix grid



Refer to the indicated section in Calabretta & Greisen (2002) for a detailed description.


This projection is defined in Calabretta & Roukema (2007).

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