Star in the constellation Cassiopeia
HD 15558
An
H-alpha image of the
Heart Nebula . HD 15558 is located at the centre of the cluster, circled.
Observation dataEpoch J2000.0 Equinox J2000.0
Constellation
Cassiopeia
Right ascension
02h 32m 42.537s [1]
Declination
61° 27′ 21.57″[1]
Apparent magnitude (V)
7.87[2]
Characteristics
Spectral type
O4.5III(f) [3] (O5.5III(f) + O7V[4] )
U−B color index
−0.55[2]
B−V color index
+0.43[2]
V−R color index
+0.38[2]
R−I color index
+0.40[2]
J−H color index
+0.18[2]
Astrometry Radial velocity (Rv ) −45.10± 1.50[5] km/sProper motion (μ) RA: −0.478[1] mas /yr Dec.: −0.849[1] mas /yr Parallax (π)0.5764 ± 0.0662 mas [1] Distance approx. 5,700 ly (approx. 1,700 pc )
Orbit Period (P)442 days[4] (1.2 [4] yr ) Semi-major axis (a)726 R ☉ [4] Eccentricity (e) 0.37± 0.07[4] Argument of periastron (ω) (secondary)120[4] °
Details Mass >152± 51[4] M ☉ Radius 16.4[6] R ☉ Luminosity ~660,000[4] L ☉ Surface gravity (log g )3.7[6] cgs Temperature 39,500[6] K Age 0.7-3[4] [7] Myr secondary Mass 46± 11[4] M ☉ Radius 5.6[6] R ☉
Other designations HD 15558,
HIP 11832,
SAO 12326,
IDS 02251+6101,
TYC 4046-44-1,
UBV 2530,
GCRV 1424,
2MASS J02324253+6127215,
WDS J02327+6127,
PPM 13720,
BD +60°502,
GSC 04046-00044,
CCDM J02327+6127,
IC 1805 148
Database references SIMBAD data
HD 15558 in the cluster IC 1805 HD 15558 (HIP 11832 ) is a massive O-type multiple star system in Cassiopeia and is specifically in our galaxy's Heart Nebula in the open cluster IC 1805 . The primary is a very massive star with 152 M ☉ and 660,000 L ☉ .
Physical characteristics [ edit ] HD 15558 A is a spectroscopic binary system containing at least two massive luminous class O stars. The primary is an O4.5 giant star with a surface temperature over 46,800 K . It has a mass of 152 M ☉ and a luminosity of 660,000 L ☉ , making it one of the most massive stars in the Milky Way Galaxy. The star loses 1.5×10−5 M ☉ per year.[7] The secondary is an O7V star. It has a mass of 46 M ☉ . The primary may itself be a double star, suggested by the improbably large mass found from the binary orbit when compared to the other stellar parameters.[4]
The Washington Double Star Catalog lists 11 companions within one arc minute of HD 15558 A, all fainter than 10th magnitude. In addition, it lists component E just over one arc minute away; it is another hot massive star, the 9th magnitude BD+60°501 with a spectral type of O7 V(n)((f))z.[3] [8]
^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties" . Astronomy and Astrophysics . 674 : A1. arXiv :2208.00211 . Bibcode :2023A&A...674A...1G . doi :10.1051/0004-6361/202243940 . S2CID 244398875 .
Gaia DR3 record for this source at VizieR .
^ a b c d e f Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues . 2237 . Bibcode :2002yCat.2237....0D .
^ a b Sota, A.; Mainz Apellantiz, J.; Morrell, N.L; Barba, R.H; Walborn, N.R; et al. (2014). "The Galactic O-star spectroscopic survey (GOSSS). II. Bright southern stars". The Astrophysical Journal Supplement . 211 (1): 10. arXiv :1312.6222 . Bibcode :2014ApJS..211...10S . doi :10.1088/0067-0049/211/1/10 . S2CID 118847528 .
^ a b c d e f g h i j k De Becker, M.; Rauw, G.; Manfroid, J.; Eenens, P. (2006). "Early-type stars in the young open cluster IC 1805. II. The probably single stars HD 15570 and HD 15629, and the massive binary/triple system HD 15558" . Astronomy & Astrophysics . 456 (3): 1121. arXiv :astro-ph/0606379 . Bibcode :2006A&A...456.1121D . doi :10.1051/0004-6361:20065300 . S2CID 16519684 . [permanent dead link ]
^ Pourbaix, D.; Tokovinin, A. A.; Batten, A. H.; Fekel, F. C.; Hartkopf, W. I.; et al. (2004). "SB9: The ninth catalogue of spectroscopic binary orbits". Astronomy & Astrophysics . 424 (2): 727–732. arXiv :astro-ph/0406573 . Bibcode :2004A&A...424..727P . doi :10.1051/0004-6361:20041213 . S2CID 119387088 .
^ a b c d Hillwig, T. C.; Gies, D. R.; Huang, W.; McSwain, M. V.; Wingert, D. W. (2006). "Binary and Multiple O-Type Stars in the Cassiopeia OB6 Association". The Astrophysical Journal . 639 (2): 1069–1080. arXiv :astro-ph/0512407 . Bibcode :2006ApJ...639.1069H . doi :10.1086/499771 . S2CID 119451956 .
^ a b Garmany, C. D.; Massey, P. (1981). "HD 15558 - an extremely luminous O-type binary star" . Publications of the Astronomical Society of the Pacific . 93 : 500. Bibcode :1981PASP...93..500G . doi :10.1086/130866 . S2CID 121457874 .
^ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog" . The Astronomical Journal . 122 (6): 3466. Bibcode :2001AJ....122.3466M . doi :10.1086/323920 .