Object X

Constellation
Triangulum

Equatorial coordinates
α = 01 33 23.715
δ = +30 25 35.107

Galactic coordinates
l = 133.5503°
b = -31.5788°

Suspected	2015^Ref
Re-classified	2015^Ref
Type	high-mass binary^Ref

Identifiers

Object X	IRAS -	GSC2.4.2 NBWQ019086	AAVSO -
SIMBAD 2MASS J01332404+3025345	Pan-STARRS 144510233487992335	SAO -	VSX -
GAIA DR3 303270801867223936	SkyMapper -	WRAY -	GCVS -
2MASS J01332404+3025345	HIP -	Hen -	BD -
WISE J013324.03+302534.5	TYC -	ESO -	HD -

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 (°)	23.3488^Ref	Parallax (mas)	0.396±0.616^Ref	Reddening E(B-V) (mag)	0.04±0.0^Ref ^{, Note}
Declination (°)	30.4264^Ref	Distance (kpc)	847±60^Ref 1.31^Ref ^{, Note} -^{, Note}
Galactic longitude (°)	133.5503^Ref	Proper motion in α (mas/yr)	-0.18±0.67^Ref
Galactic latitude (°)	-31.5788^Ref	Proper motion in δ (mas/yr)	-0.53±0.48^Ref

Links

SIMBAD CDS Portal

Notes

Object X is identified as the most luminous infrared star in M33, characterized by a composite nature with a hot, luminous O-B star component and a cool, dust-enshrouded companion. Described as a very young and massive binary star, it was referred to as a "super symbiotic binary" in Mikołajewska et al. (2015). However, it is noted that it does not fulfill the criteria for symbiotic binaries, leading to a classification as a related object, but not a symbiotic star.

References

Khan, R., Stanek, K. Z., Kochanek, C. S. et al., 2011, ApJ, 732, 1, 43, 2011ApJ...732...43K
Mikołajewska, J., Caldwell, N., Shara, M. M. et al., 2015, ApJL, 799, 2, L16, 2015ApJ...799L..16M