Th 3-18

CONFIRMED MILKY WAY

Constellation
Ophiucus

Equatorial coordinates
α = 17 28 26.924
δ = -28 38 34.717

Galactic coordinates
l = 358.2276°
b = 3.3318°

Suspected	1979^Ref
Confirmed	1984^Ref
Symbiotic IR type	S^Ref
Hot component type	shell-burning^Ref
Outbursts	-

Identifiers

Th 3-18	IRAS -	GSC2.4.2 S8G8039602	AAVSO 000-BJT-834
SIMBAD PN Th 3-18	Pan-STARRS 73622621122188720	SAO -	VSX 241041
GAIA DR3 4059655594297061888	SkyMapper 172826.93-283834.5	WRAY 17-83	GCVS -
2MASS J17282693-2838345	HIP -	Hen 2-228	BD -
WISE J172826.93-283834.6	TYC -	ESO 454-32	HD -

Symbiotic Catalogs

Bidelman (1954)	-	Allen (1984)	Th3-18 (Conf.)	Belzcyński et al. (2001)	Th 3-18 (Conf.)
Gaposchkin (1957)	-	Kenyon (1986)	Th3-18 (Conf.)	Akras et al. (2019)	PN Th 3-18 (Conf.)
Boyarchuk (1969)	-	Vaidis (1988, 1991)	Th-3-18 (Conf.)

Position

Right ascension (°)	262.1122^Ref	Parallax (mas)	0.152±0.040^Ref	Reddening E(B-V) (mag)	1.14±0.02^Ref ^{, Note}
Declination (°)	-28.6430^Ref	Distance (kpc)	3.5^Ref, 4.2^Ref 5.07^Ref ^{, Note}, 4.75^Ref ^{, Note}
Galactic longitude (°)	358.2276^Ref	Proper motion in α (mas/yr)	-4.04±0.05^Ref
Galactic latitude (°)	3.3318^Ref	Proper motion in δ (mas/yr)	-4.97±0.04^Ref

Observations

X-Ray	No^Ref	IR type	S^Ref	Radio	No^Ref
X-Ray type	-	J (mag)	9.82^Ref	Flickering	-
GALEX FUV (mag)	-	H (mag)	8.67^Ref	Outbursts	-
GALEX NUV (mag)	-	K (mag)	8.23^Ref	Outburst type	-
IUE	No^Ref	WISE W1 (mag)	8.01^Ref	Jets	-
FUSE	No^Ref	WISE W2 (mag)	7.98^Ref	Resolved nebula	-
U (mag)	-	WISE W3 (mag)	7.71^Ref	IPmax (eV)	114^Ref
B (mag)	-	WISE W4 (mag)	7.10^Ref	[O III] lines	Yes?^Ref
V (mag)	15.30^Ref	IRAS 12μm (Jy)	-	He II lines	Yes^Ref
R (mag)	15.44^Ref	IRAS 25μm (Jy)	-	[Fe VII] lines	No^Ref
I (mag)	-	IRAS 60μm (Jy)	-	O VI lines	Yes^Ref
BP (mag)	16.15^Ref	IRAS 100μm (Jy)	-
G (mag)	13.91^Ref	AKARI S09 (Jy)	-
RP (mag)	12.53^Ref	AKARI S18 (Jy)	-

Orbit

Orbital period (days)	-	γ velocity (km/h)	122.84±0.68^Ref	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	M2 III^Ref, M3 III^Ref, M2 III^Ref	Mass (M_⊙)	-	Pulsation	-
Eff. temperature (K)	3649^Ref	Radius (R_⊙)	-	Type	-
IR type	S^Ref	Luminosity (L_⊙)	-	Pulsation period (days)	-
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)	-	Luminosity (L_⊙)	750^Ref
Lower limit (K)	114000^Ref
Upper limit (K)	-

Links

SIMBAD CDS Portal

Notes

Allen (1984) and Stenholm & Acker (1987) detected emission lines with ionization potential up to 114 eV.

References

Allen, D. A., 1979, Obs, 99, 83, 1979Obs....99...83A
Allen, D. A., 1980, MNRAS, 192, 521, 1980MNRAS.192..521A
Allen, D. A., 1984, PASA, 5, 3, 369, 1984PASA....5..369A
Medina Tanco, G. A., Steiner, J. E., 1995, AJ, 109, 1770, 1995AJ....109.1770M
Mikołajewska, J., Acker, A., Stenholm, B., 1997, A&A, 327, 191, 1997A&A...327..191M
Stenholm, B., Acker, A., 1987, A&AS, 68, 51, 1987A&AS...68...51S

Last updated: April 17, 2022