It seems that NGC 4460 system hasn’t been discussed as discordant redshift system before. NGC 4460 has a high redshift object (object 2, z = 0.173) within its disk. NED says this about object 2: “This is part of the galaxy NGC 4460. Either z or Dxd is incorrect.” Quite confident statement considering that object 2’s appearance is not something you would expect to see in NGC 4460’s disk, and fits rather well with a background galaxy shining through NGC 4460’s disk.
Object 3 also has discordant redshift compared to NGC 4460, and it is very close to NGC 4460. There’s nothing apparent to suggest interaction in the system, so this seems to be genuine background object (also the appearance of object 3 suggests background galaxy in my opinion).
Notes
Only two additional redshifts are available in the field despite it being within SDSS coverage area. Object 4 has similar redshift to NGC 4460, so apparently it is an object of NGC 4460’s disk. Additionally there’s one star in the field. Both of these redshifts are in SDSS DR9 and they are not yet available in NED.
Figure 1. The objects with measured redshifts near NGC 4460. Size of the image is about 6.8 x 6.8 arcmin. Image is from Sloan Digital Sky Survey. Click for larger version of the image.
Objects and their data
NBR | NAME | TYPE | REDSHIFT | MAG | SEPARATION |
1 | NGC 4460 | SB(s)0+? sp | 0.001634 (490 km/s) | 12.26 | 0 |
2 | SDSS J122848.76+445208.7 | galaxy | 0.172950 | 15.2 (g) | 0.638 |
3 | SDSS J122842.63+445230.3 | galaxy | 0.066883 (20051 km/s) | 18.0 (g) | 0.833 |
4 | SDSS J122841.41+445054.9 | part of galaxy | (544 km/s) | 20.92 (g) | 1.188 |
NED objects with measured redshifts within 10′ from NGC 4460
Filed under: DRS |
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