leda Compilation of position angles

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This catalogue (table a103 in the database) presents the compilation of the position angles for galaxies. The position angle of the major axis is counted in degrees (0 to 180) from the North to the East: PA=0 corresponds to a galaxy whose longest axis is oriented North-South.

Galaxies are not pure ellipsoids and therefore the position angles may varies with the considered surface brightness level. In some cases, this isophote twist may be very important, as for example in some spiral galaxies where a bar, seen at hight surface brightness, may be orthogonal to the outer disk. HyperLeda does not store information about the internal change of the position angle nor even information about the isophotal level where this quantity was measured.

Field: p_a

Positional Angle, measured value with a quality flag given in the parentheses.

HyperLeda Questions: leda@univ-lyon1.fr