IC 1257

Globular Cluster IC 1257, in Ophiuchus

RA:
17:27:08.5
Dec:
-07:05:35
Distance from Sun:
81.5 kly
Distance from Galactic Center:
58.4 kly
Apparent Diameter:
arc min
Brightness:
13.10 mag vis
Radial Velocity:
-140.2 +/- 2.1 km/s
Diameter:
ly
Abs. Mag:
-6.15 Mag vis
Discovered in 1890 by Spitaler.
Identified as globular cluster by W.E. Harris et.al in 1997.

On the ground of its discovery by Rudolf Ferdinand Spitaler, this object was included by Dreyer in his first Index Catalogue as IC 1257, and longly referred to as an open cluster, although R. Burnham, Jr. remarked that its classification may be uncertain. It was finally revealed as a globular cluster only in 1997 (Harris et.al., 1997), making it Milky Way Globular Cluster No. 147.

Identification as a globular was done by obtaining a color-magnitude diagram, which immediately revealed its nature as a globular beyond the Galactic Center. IC 1257 is at a distance of 81,500 light years from our Sun and about 58,400 light years from the Galactic Center. It is approaching us at about 140 km/sec.

References:


[MW Globulars] | [NGC] | [DSS] | [SIMBAD] | [ADS] | [GGC-DB]
Hartmut Frommert [contact]
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