POSSIBLE
NGC 205
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| NGC 205 SySt-2 | IRAS - | GSC2.4.2 NBWB112295 | AAVSO - |
| SIMBAD [MMD2006] 2647 | Pan-STARRS - | SAO - | VSX - |
| GAIA DR3 - | SkyMapper - | WRAY - | GCVS - |
| 2MASS - | HIP - | Hen - | BD - |
| WISE - | TYC - | ESO - | HD - |
| Bidelman (1954) | - | Allen (1984) | - | Belzcyński et al. (2001) | - |
| Gaposchkin (1957) | - | Kenyon (1986) | - | Akras et al. (2019) | NGC 205 SySt-2 (Susp.) |
| Boyarchuk (1969) | - | Vaidis (1988, 1991) | - |
| Right ascension (°) | 10.0333Ref | Parallax (mas) | - | Reddening E(B-V) (mag) | 0.06±0.0Ref, Note |
| Declination (°) | 41.7567Ref | Distance (kpc) | 824±27Ref -, Note |
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| Galactic longitude (°) | 120.6730Ref | Proper motion in α (mas/yr) | - | ||
| Galactic latitude (°) | -21.0654Ref | Proper motion in δ (mas/yr) | - |
| X-Ray | - | IR type | - | Radio | - |
| X-Ray type | - | J (mag) | - | Flickering | - |
| GALEX FUV (mag) | - | H (mag) | - | Outbursts | - |
| GALEX NUV (mag) | - | K (mag) | - | Outburst type | - |
| IUE | NoRef | WISE W1 (mag) | - | Jets | - |
| FUSE | NoRef | WISE W2 (mag) | - | Resolved nebula | - |
| U (mag) | - | WISE W3 (mag) | - | IPmax (eV) | 54.9Ref |
| B (mag) | - | WISE W4 (mag) | - | [O III] lines | YesRef |
| V (mag) | 24.85Ref | IRAS 12μm (Jy) | - | He II lines | YesRef |
| R (mag) | - | IRAS 25μm (Jy) | - | [Fe VII] lines | NoRef |
| I (mag) | - | IRAS 60μm (Jy) | - | O VI lines | NoRef |
| BP (mag) | - | IRAS 100μm (Jy) | - | ||
| G (mag) | - | AKARI S09 (Jy) | - | ||
| RP (mag) | - | AKARI S18 (Jy) | - |
| Orbital period (days) | - | 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 | K5-M2Ref | Mass (M⊙) | - | Pulsation | - |
| Eff. temperature (K) | - | Radius (R⊙) | - | Type | - |
| IR type | - | Luminosity (L⊙) | - | Pulsation period (days) | - |
| 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) | 340000Ref | Luminosity (L⊙) | - | ||
| Lower limit (K) | - | ||||
| Upper limit (K) | - |
NGC 205 SySt-2 exhibits an extremely intense He II 4686 Å emission line, indicating that the effective temperature of the star ionizing the gas should be tremendously high. According to Gonçalves et al. (2015), it is puzzling that higher ionization forbidden lines are not detected in its spectrum. If confirmed as a true symbiotic binary, NGC 205 SySt-2 will be one of the few symbiotics that shows the Ne VII Raman scattering line at 4881 Å.