New Online Database of Symbiotic Variables: NGC 6822 SySt-1

Constellation
Sagittarius

Equatorial coordinates
α = 19 44 53.880
δ = -14 51 47.157

Galactic coordinates
l = 25.2754°
b = -18.4095°

Suspected	2009^Ref
Confirmed	2009^Ref
Symbiotic IR type	S^Ref
Hot component type	shell-burning^Ref
Outbursts	-

Identifiers

NGC 6822 SySt-1	IRAS -	GSC2.4.2 SA0E055910	AAVSO -
SIMBAD [SRC2012] 296.224487-14.863070	Pan-STARRS 90162962244434685	SAO -	VSX -
GAIA DR3 4182446338325490816	SkyMapper -	WRAY -	GCVS -
2MASS J19445377-1451463	HIP -	Hen -	BD -
WISE J194453.82-145146.6	TYC -	ESO -	HD -

Symbiotic Catalogs

Bidelman (1954)	-	Allen (1984)	-	Belzcyński et al. (2001)	-
Gaposchkin (1957)	-	Kenyon (1986)	-	Akras et al. (2019)	NGC6822 SySt-1 (Conf.)
Boyarchuk (1969)	-	Vaidis (1988, 1991)	-

Position

Right ascension (°)	296.2245^Ref	Parallax (mas)	0.060±0.841^Ref	Reddening E(B-V) (mag)	0.21±0.01^Ref ^{, Note}
Declination (°)	-14.8631^Ref	Distance (kpc)	500±10^Ref 5.12^Ref ^{, Note}, 2.63^Ref ^{, Note}
Galactic longitude (°)	25.2754^Ref	Proper motion in α (mas/yr)	-1.48±0.99^Ref
Galactic latitude (°)	-18.4095^Ref	Proper motion in δ (mas/yr)	-1.53±0.83^Ref

Observations

X-Ray	No^Ref	IR type	S^Ref	Radio	-
X-Ray type	-	J (mag)	-	Flickering	-
GALEX FUV (mag)	-	H (mag)	-	Outbursts	-
GALEX NUV (mag)	-	K (mag)	-	Outburst type	-
IUE	No^Ref	WISE W1 (mag)	14.55^Ref	Jets	-
FUSE	No^Ref	WISE W2 (mag)	14.88^Ref	Resolved nebula	-
U (mag)	22.64^Ref	WISE W3 (mag)	12.28^Ref	IPmax (eV)	114^Ref
B (mag)	22.82^Ref	WISE W4 (mag)	8.84^Ref	[O III] lines	No^Ref
V (mag)	21.62^Ref	IRAS 12μm (Jy)	-	He II lines	Yes^Ref
R (mag)	-	IRAS 25μm (Jy)	-	[Fe VII] lines	No^Ref
I (mag)	-	IRAS 60μm (Jy)	-	O VI lines	Yes^Ref
BP (mag)	21.04^Ref	IRAS 100μm (Jy)	-
G (mag)	20.35^Ref	AKARI S09 (Jy)	-
RP (mag)	19.02^Ref	AKARI S18 (Jy)	-

Orbit

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	-

Cool component

Spectral type	C^Ref	Mass (M_⊙)	-	Pulsation	Yes^Ref
Eff. temperature (K)	-	Radius (R_⊙)	-	Type	SR^Ref
IR type	S^Ref	Luminosity (L_⊙)	-	Pulsation period (days)	142±3^Ref
Metallicity [Fe/H]	-			Pulsation ephemeris	-

Hot component

Type/Spectral type	WD?^Ref	Mass (M_⊙)	-	Spin period (min)	-
Shell-burning/Accreting-only	shell-burning^Ref	Radius (R_⊙)	-	Accretion disk	-
Eff. temperature (K)	130000^Ref	Luminosity (L_⊙)	-
Lower limit (K)	-
Upper limit (K)	-

Links

SIMBAD CDS Portal

Notes

This object is identified as an S-type symbiotic star, consisting of an AGB carbon star, and a compact companion, likely a white dwarf. The red giant exhibits characteristics of a semiregular variable, pulsating in the first overtone with a period of 142 days (Kniazev et al., 2009).

References

Akras, S., Guzman-Ramirez, L., Leal-Ferreira, M. L. et al., 2019, ApJS, 240, 2, 21, 2019ApJS..240...21A
Kniazev, A. Y., Väisänen, P., Whitelock, P. A. et al., 2009, MNRAS, 395, 2, 1121, 2009MNRAS.395.1121K
Massey, P., Mcneill, R. T., Olsen, K. A. G. et al., 2007, AJ, 134, 6, 2474, 2007AJ....134.2474M

NGC 6822 SySt-1