LIKELY
M31
|
| M31SyS J004322.50+413940.9 | IRAS - | GSC2.4.2 NBW9006917 | AAVSO - |
| SIMBAD LGGS J004322.50+413940.9 | Pan-STARRS 157990108436384225 | SAO - | VSX - |
| GAIA DR3 381299259441348736 | SkyMapper - | WRAY - | GCVS - |
| 2MASS J00432249+4139409 | HIP - | Hen - | BD - |
| WISE J004322.64+413941.0 | TYC - | ESO - | HD - |
| Bidelman (1954) | - | Allen (1984) | - | Belzcyński et al. (2001) | - |
| Gaposchkin (1957) | - | Kenyon (1986) | - | Akras et al. (2019) | M31 SySt-19 (Susp.) |
| Boyarchuk (1969) | - | Vaidis (1988, 1991) | - |
| Right ascension (°) | 10.8437Ref | Parallax (mas) | 0.355±0.459Ref | Reddening E(B-V) (mag) | 0.26±0.03Ref, Note |
| Declination (°) | 41.6613Ref | Distance (kpc) | 785±25Ref 2.22Ref, Note, 4.73Ref, Note |
||
| Galactic longitude (°) | 121.3169Ref | Proper motion in α (mas/yr) | 1.10±0.42Ref | ||
| Galactic latitude (°) | -21.1851Ref | Proper motion in δ (mas/yr) | 0.17±0.38Ref |
| X-Ray | NoRef | IR type | S?Ref | Radio | - |
| X-Ray type | - | J (mag) | - | Flickering | - |
| GALEX FUV (mag) | - | H (mag) | - | Outbursts | Yes?Ref |
| GALEX NUV (mag) | - | K (mag) | - | Outburst type | - |
| IUE | NoRef | WISE W1 (mag) | 15.72Ref | Jets | - |
| FUSE | NoRef | WISE W2 (mag) | 15.81Ref | Resolved nebula | - |
| U (mag) | 20.69Ref | WISE W3 (mag) | 12.61Ref | IPmax (eV) | 13.6Ref |
| B (mag) | 21.19Ref | WISE W4 (mag) | 9.25Ref | [O III] lines | NoRef |
| V (mag) | 20.35Ref | IRAS 12μm (Jy) | - | He II lines | NoRef |
| R (mag) | 19.90Ref | IRAS 25μm (Jy) | - | [Fe VII] lines | NoRef |
| I (mag) | 19.10Ref | IRAS 60μm (Jy) | - | O VI lines | NoRef |
| BP (mag) | 20.31Ref | IRAS 100μm (Jy) | - | ||
| G (mag) | 19.97Ref | AKARI S09 (Jy) | - | ||
| RP (mag) | 19.08Ref | AKARI S18 (Jy) | - |
| Orbital period (days) | ~900?Ref | γ velocity (km/h) | - | Size of giant’s orbit (AU) | - |
| Eccentricity | - | RV of giant (km/h) | - | Separation (AU) | - |
| Inclination (°) | - | Inferior conj. of giant (JD) | - | Mass function | - |
| Eclipses | - | Mass ratio | - | ||
| Orbital ephemeris | - |
| Spectral type | M4Ref | Mass (M⊙) | - | Pulsation | YesRef |
| Eff. temperature (K) | - | Radius (R⊙) | - | Type | low-amplitude SR?Ref |
| IR type | S?Ref | Luminosity (L⊙) | - | Pulsation period (days) | ~80?Ref |
| Metallicity [Fe/H] | - | Pulsation ephemeris | - |
| Type/Spectral type | - | Mass (M⊙) | - | Spin period (min) | - |
| Shell-burning/Accreting-only | shell-burning?Ref | Radius (R⊙) | - | Accretion disk | - |
| Eff. temperature (K) | - | Luminosity (L⊙) | - | ||
| Lower limit (K) | 14000Ref | ||||
| Upper limit (K) | - |
Classified as a suspected symbiotic binary in Mikołajewska et al. (2014), the object shows a very rich, low-excitation emission line spectrum, including H I, numerous Fe II and [Fe II], and Na I D, along with very strong Ca II T lines. H I and other permitted lines display P Cyg profiles with an absorption component blueshifted by ∼350 km/s with respect to the emission peak. The ∼900-day period reported by An et al. (2004) very likely represents orbital variation. The shorter period P ∼80 days (Vilardell et al., 2006) may be attributed to low-amplitude SR pulsation of the red giant.