Hu 2-1
SUSPECTED
MILKY WAY
Constellation
Hercules |
Equatorial coordinates
α = 18 49 47.560
δ = +20 50 39.272 |
Galactic coordinates
l = 51.4835°
b = 9.6845° |
| Suspected |
2001Ref |
| Confirmed |
- |
| Symbiotic IR type |
D?Ref |
| Hot component type |
shell-burning?Ref |
| Outbursts |
- |
|
|
Symbiotic Catalogs
| Bidelman (1954) |
- |
Allen (1984) |
- |
Belzcyński et al. (2001) |
- |
| Gaposchkin (1957) |
- |
Kenyon (1986) |
- |
Akras et al. (2019) |
- |
| Boyarchuk (1969) |
- |
Vaidis (1988, 1991) |
- |
Position
| Right ascension (°) |
282.4482Ref |
Parallax (mas) |
0.419±0.066Ref |
Reddening E(B-V) (mag) |
0.27±0.01Ref, Note |
| Declination (°) |
20.8442Ref |
Distance (kpc) |
2.37Ref, Note, 2.18Ref, Note |
|
|
| Galactic longitude (°) |
51.4835Ref |
Proper motion in α (mas/yr) |
-0.89±0.04Ref |
|
|
| Galactic latitude (°) |
9.6845Ref |
Proper motion in δ (mas/yr) |
-7.84±0.05Ref |
|
|
Observations
| X-Ray |
- |
IR type |
D?Ref |
Radio |
YesRef |
| X-Ray type |
- |
J (mag) |
11.16Ref |
Flickering |
- |
| GALEX FUV (mag) |
- |
H (mag) |
11.20Ref |
Outbursts |
- |
| GALEX NUV (mag) |
- |
K (mag) |
10.43Ref |
Outburst type |
- |
| IUE |
YesRef |
WISE W1 (mag) |
9.37Ref |
Jets |
- |
| FUSE |
NoRef |
WISE W2 (mag) |
8.34Ref |
Resolved nebula |
- |
| U (mag) |
- |
WISE W3 (mag) |
3.11Ref |
IPmax (eV) |
- |
| B (mag) |
12.37Ref |
WISE W4 (mag) |
-0.06Ref |
[O III] lines |
- |
| V (mag) |
13.30Ref |
IRAS 12μm (Jy) |
2.09Ref |
He II lines |
- |
| R (mag) |
12.30Ref |
IRAS 25μm (Jy) |
12.20Ref |
[Fe VII] lines |
- |
| I (mag) |
- |
IRAS 60μm (Jy) |
6.99Ref |
O VI lines |
- |
| BP (mag) |
11.42Ref |
IRAS 100μm (Jy) |
4.38Ref |
|
|
| G (mag) |
12.82Ref |
AKARI S09 (Jy) |
0.78Ref |
|
|
| RP (mag) |
11.13Ref |
AKARI S18 (Jy) |
5.68Ref |
|
|
Orbit
| Orbital period (days) |
9125-29200Ref |
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 |
- |
|
|
|
|
Cool component
| Spectral type |
- |
Mass (M⊙) |
- |
Pulsation |
- |
| Eff. temperature (K) |
- |
Radius (R⊙) |
- |
Type |
- |
| IR type |
D?Ref |
Luminosity (L⊙) |
- |
Pulsation period (days) |
- |
| Metallicity [Fe/H] |
- |
|
|
Pulsation ephemeris |
- |
Hot component
| 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) |
- |
|
|
|
|
| Upper limit (K) |
- |
|
|
|
|
Notes
A possible link to symbiotic binaries was suggested by Miranda et al. (2001), related to a possible symbiotic outflow.
References
- Miranda, L. F., Torrelles, J. M., Guerrero, M. A. et al., 2001, MNRAS, 321, 3, 487, 2001MNRAS.321..487M
Last updated: August 20, 2021