SSSPM J1549-3544 is a star in the constellation Lupus with high proper motion. It was initially found to have high proper motion in a 2003 survey of images taken by the optical SuperCOSMOS Sky Surveys and by the near-infrared sky surveys 2MASS and DENIS. It was then thought to be a cool white dwarf close to the Sun.[3] However, more detailed spectroscopic observations in 2005 appear to show that it is not a white dwarf, but a high-velocity halo metal-poor subdwarf.[2]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Lupus |
| Right ascension | 15h 48m 40.172s[1] |
| Declination | −35° 44′ 26.17″[1] |
| Apparent magnitude (V) | 14.78[2] |
| Characteristics | |
| Spectral type | sdK5[2] |
| Astrometry | |
| Proper motion (μ) | RA: −597.714[1] mas/yr Dec.: −535.841[1] mas/yr |
| Parallax (π) | 10.4127 ± 0.0214 mas[1] |
| Distance | 313.2 ± 0.6 ly (96.0 ± 0.2 pc) |
| Absolute magnitude (MV) | 9.5 |
| Details | |
| Radius | 0.30[1] R☉ |
| Luminosity | 0.02[1] L☉ |
| Surface gravity (log g) | 5.0[1] cgs |
| Temperature | 3,956[1] K |
| Metallicity [Fe/H] | −1.28[1] dex |
| Other designations | |
SSSPM J1549-3544, 2MASS J15484023-3544254 | |
| Database references | |
| SIMBAD | data |
References
edit- ^ a b c d e f g h i j Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c Farihi, J.; Wood, P. R.; Stalder, B. (2005). "SSSPM J1549-3544 is Not a White Dwarf". The Astrophysical Journal. 627 (1): L41–L43. arXiv:astro-ph/0505525. Bibcode:2005ApJ...627L..41F. doi:10.1086/432158. S2CID 10645235.
- ^ Scholz, R. -D; Lehmann, I.; Matute, I.; Zinnecker, H. (2004). "The nearest cool white dwarf (D ∼4 pc), the coolest M-type subdwarf (SdM9.5), and other high proper motion discoveries". Astronomy and Astrophysics. 425: 519–527. arXiv:astro-ph/0406457. Bibcode:2004A&A...425..519S. doi:10.1051/0004-6361:20041059. S2CID 9352481.
 | This subdwarf star-related article is a stub. You can help Wikipedia by expanding it. |