UGC 06970 – Discordant redshift pair

UGC 06970 system was included to Karachentsev’s 1972 “Catalogue of Isolated Pairs of Galaxies in the Northern Hemisphere” as KPG 315 (Karachentsev, 1972). Karachentsev gave redshifts for all the pairs in the catalog, and this pair had discordant redshift. The main galaxy has radial velocity of cz = 1327 km/s while the smaller companion in the outskirts of the main galaxy disk had cz = 6230 km/s in his catalog. Tifft (1982) confirmed the redshifts of the pair.

Notes

– It can be seen from SDSS image below, that object 2 is projected partially within UGC 6970 disk area. In that sense this system resembles more famous NGC 450.

– Objects 3 (z = 0.391) and 6 (z = 0.188) are roughly aligned across UGC 6970.

– Objects 4 (z = 0.081) and 7 (z = 0.052) are roughly aligned across UGC 6970. However, object 7 is better aligned with object 13 (z = 0.096). Object 5 is close to object 7 and has similar redshift, so they might form a physical galaxy pair in traditional sense.


Figure 1. The objects with measured redshifts near UGC 06970. Size of the image is 10 x 10 arcmin. Image is from Sloan Digital Sky Survey.

Objects and their data

NBR NAME TYPE REDSHIFT MAG SEPARATION
1 UGC 06970 SBm 0.004924 (1476 km/s) 14.7 0
2 KPG 315B Sb 0.021398 (6415 km/s) 16.7 (g) 0.299
3 SDSS J115844.96-012525.6 galaxy 0.391020 20.6 (g) 2.266
4 2dFGRS N313Z127 galaxy 0.080500 18.61 2.391
5 SDSS J115851.22-012938.2 galaxy 0.052167 18.7 (g) 2.394
6 SDSS J115846.53-013016.4 galaxy 0.187671 18.8 (g) 2.596
7 SDSS J115853.36-012933.4 galaxy 0.052400 18.9 (g) 2.684
8 SDSS J115856.03-012549.5 galaxy 0.052032 16.9 (g) 3.189
9 SDSS J115859.35-012616.6 galaxy 0.166072 19.45 3.699
10 SDSS J115902.10-012549.1 QSO 1.234500 20.7 (g) 4.513
11 SDSS J115837.90-012307.8 galaxy 0.083736 17.4 (g) 4.951
12 [VCV2001] J115904.8-012506 QSO 1.151000 20.19 5.459
13 SDSS J115829.59-012356.2 galaxy 0.096322 18.2 (g) 5.495

NED objects within 10′ from UGC 6970
SDSS image of the system.

References

Karachentsev I.D., 1972, Publ. of the Special Astrophy. Observatory of USSR AS, No. 7, “Catalogue of Isolated Pairs of Galaxies in the Northern Hemisphere”

Tifft, W. G., 1982, ApJS, 50, 319-389, “Double galaxy investigations. I – Observations”

Advertisements