4U 1954+31

Constellation
Cygnus

Equatorial coordinates
α = 19 55 42.336
δ = +32 05 48.949

Galactic coordinates
l = 68.3919°
b = 1.9269°

Suspected	2006^Ref
Re-classified	2020^Ref
Type	HMXB^Ref

Identifiers

4U 1954+31	IRAS 19537+3157	GSC2.4.2 N2GO303767	AAVSO 000-BKR-938
SIMBAD 4U 1954+31	Pan-STARRS 146512989264226929	SAO -	VSX 286292
GAIA DR3 2034031438383765760	SkyMapper -	WRAY -	GCVS -
2MASS J19554232+3205492	HIP -	Hen -	BD -
WISE J195542.33+320548.8	TYC 2673-2004-1	ESO -	HD -

Symbiotic Catalogs

Bidelman (1954)	-	Allen (1984)	-	Belzcyński et al. (2001)	-
Gaposchkin (1957)	-	Kenyon (1986)	-	Akras et al. (2019)	4U 1954+31 (Conf.)
Boyarchuk (1969)	-	Vaidis (1988, 1991)	-

Position

Right ascension (°)	298.9264^Ref	Parallax (mas)	0.258±0.025^Ref	Reddening E(B-V) (mag)	1.5±0.06^Ref ^{, Note}
Declination (°)	32.0969^Ref	Distance (kpc)	3.43^Ref ^{, Note}, 3.34^Ref ^{, Note}
Galactic longitude (°)	68.3919^Ref	Proper motion in α (mas/yr)	-2.16±0.02^Ref
Galactic latitude (°)	1.9269^Ref	Proper motion in δ (mas/yr)	-6.07±0.03^Ref

Links

SIMBAD CDS Portal

Notes

Initially thought to be a low-mass X-ray binary with a red giant and a neutron star (symbiotic X-ray binary), it was reclassified as a high-mass X-ray binary by Hinkle et al. (2020).

References

Enoto, T., Sasano, M., Yamada, S. et al., 2014, ApJ, 786, 2, 127, 2014ApJ...786..127E
Hinkle, K. H., Lebzelter, T., Fekel, F. C. et al., 2020, ApJ, 904, 2, 143, 2020ApJ...904..143H
Marcu, D. M., Fürst, F., Pottschmidt, K. et al., 2011, ApJL, 742, 1, L11, 2011ApJ...742L..11M
Masetti, N., Orlandini, M., Palazzi, E. et al., 2006, A&A, 453, 1, 295, 2006A&A...453..295M
Masetti, N., Rigon, E., Maiorano, E. et al., 2007, A&A, 464, 1, 277, 2007A&A...464..277M
Mattana, F., Götz, D., Falanga, M. et al., 2006, A&A, 460, 2, L1, 2006A&A...460L...1M