System | Description |
B1950 | Equatorial coordinates, Besselian, Equinox 1950.0, Epoch 2000.0 |
J2000 | Equatorial coordinates, Julian, Equinox 2000.0, Epoch 2000.0 |
G |
Galactic coordinates in the reference frame called
"new" system, adopted by IAU in 1958. Galactic pole at
B124900.0+272400, node at ra=282.25,l=33 deg (inclination 62.6 deg).
The B1950 north celestial pole is at l=123, b=27.4 deg.
|
SG | Supergalactic coordinates.
Supergalactic equator is conceptually defined by the plane
of the local (Virgo-Hydra-Centaurus) supercluster, and the
origin of supergalactic longitude is at the intersection
of the supergalactic and galactic planes. See the definition
in RC2 (de Vaucouleurs et al. 1976) and RC3 (de Vaucouleurs et al. 1991):
North SG pole at l=47.37 deg, b=6.32 deg. Node at
l=137.37, sgl=0 (inclination 83.68 deg).
Note: The position of the SG node reported in RC2 (137.29
deg) differs from RC3 (137.37 deg; see page 12, the difference
is mentioned but not commented).
|
The precision of the position is coded in the flag