NGC 1557
(ESO 055 15)
0.25
UTI
0.27
CN
0.0
Cdens
1.0
CC3
0.0
Clit
1.0
Cdup
Radius (P>50% members)
7.1 [arcmin]
- CN 0.27 Poorly populated
- Cdens 0.0 Very loose
- CC3 1.0 Very high quality
- Clit 0.0 Rarely studied
- Cdup 1.0 Unique
Overview
NGC 1557 is a poorly populated, very loose object of very high C3 quality. Its parallax locates it at a very large* distance, well below the mid-plane, affected by low extinction. It is catalogued as an old cluster (see Parameters). It is rarely studied in the literature, with no articles listed in the last 7 years.
(*): The parallax distance estimate (~67.57 kpc) differs significantly from the median photometric distance (~1.05 kpc).
Relatively close
Low extinction
Old
Data
| Reference | Year | RA [deg] | DEC [deg] | Plx [mas] | pmRA [mas/yr] | pmDE [mas/yr] | Rv [km/s] |
|---|---|---|---|---|---|---|---|
| UCC | â | 63.158 | -70.488 | 0.015 | 1.883 | -0.434 | 270.978 |
| Bica et al. | 2019 | 63.301 | -70.47 | â | â | â | â |
| Dias et al. | 2014 | 63.296 | -70.472 | â | 2.71 | 5.53 | 4.96 |
| Dias et al. | 2002 | 63.296 | -70.472 | â | 2.86 | 5.71 | 4.96 |
đĄ Note: The UCC values are estimated from its identified members.
| Reference | Year | Dist [kpc] | Av [mag] | DAv [mag] | Age [Myr] | [Fe/H] [dex] | Mass [Msun] | Bfr | BSS |
|---|---|---|---|---|---|---|---|---|---|
| Dias et al. | 2002 | 1.05 | 0.34 | â | 3020 | â | â | â | â |
Cantat-Gaudin et al. (2020)
Not in WEBDA and classified as non-existent in early catalogues; later works list it as a cluster remnant with highly discrepant distance estimates. More details in Appendix A of the article.