KQ Puppis

From HandWiki - Reading time: 7 min


Short description: Triple star in the constellation Puppis
KQ Puppis
250px
KQ Puppis is the bright red star on the right, with Messier 47 to its left (east) and Messier 46 even further east.
Observation data
Equinox J2000.0]] (ICRS)
Constellation Puppis
Right ascension  07h 33m 47.96383s[1]
Declination −14° 31′ 26.0026″[1]
Apparent magnitude (V) +4.97[2] (4.82 - 5.17[3])
Characteristics
KQ Pup A
Evolutionary stage Red supergiant[4]
Spectral type M2Iab[5]
U−B color index +0.29[2]
B−V color index +1.41[2]
Variable type Slow irregular variable[3]
KQ Pup B
Evolutionary stage Main sequence[4]
Spectral type B2V + (A/F)V[4]
Astrometry
Radial velocity (Rv)+34.4[4] km/s
Proper motion (μ) RA: -7[6] mas/yr
Dec.: +4[6] mas/yr
Parallax (π)1.29 ± 0.10[4] mas
Distance2,500 ± 200 ly
(780 ± 60 pc)
Orbit[4]
PrimaryKQ Pup Ba
CompanionKQ Pup Bb
Period (P)17.2596 days
Semi-major axis (a)0.3 au
Eccentricity (e)≥0.236
Inclination (i)~90°
Orbit[4]
PrimaryKQ Pup A
CompanionKQ Pup B
Period (P)9,500 days
Semi-major axis (a)24.89±1.48 au
Eccentricity (e)0.62±0.01
Inclination (i)70.3±1.2°
Longitude of the node (Ω)319.3±3.6°
Periastron epoch (T)60,310 MJD
Argument of periapsis (ω)
(primary)
203.5±2.2°
Semi-amplitude (K1)
(primary)
17.1 km/s
Details[4]
KQ Pup A
Mass9.12+1.73
−1.53
 M
Radius491+41
−36
 R
Luminosity38,000+7,700
−4,900
 L
Temperature3,660±170 K
Age18.7–46.9 Myr
KQ Pup Ba
Mass7.5–11.5 M
Luminosity8,900 L
Temperature19,900 K
Rotational velocity (v sin i)190±70 km/s
Age18.7–46.9 Myr
KQ Pup Bb
Mass4.4+3.7
−3.2
 M
Age18.7–46.9 Myr
Other designations
KQ Pup, BD−14°1971, HIP 36773, HR 2902, NGC 2422 9, SAO 153072
KQ Pup A: HD 60414
KQ Pup B: HD 60415
Database references
SIMBADdata

KQ Puppis is a triple star[4] system in the constellation of Puppis. With an apparent magnitude varying between 4.82 and 5.17, it is faintly visible to the naked eye under skies with little to no luminous pollution. Based on dynamical parallax measurements, it is located at a distance of 2,500 light-years (770 parsecs).

Characteristics

A light curve for KQ Puppis, plotted from Hipparcos data[7]

The KQ Puppis system consists of three stars in a hierarchical configuration (i.e. a compact binary around a third component). The primary component, KQ Puppis A, is a red supergiant with around nine times the mass of the Sun, and 490 times the Sun's radius. It radiates 38,000 times the Sun's luminosity from its photosphere at an effective temperature of 3,660 K.[4] It shows small amplitude irregular pulsations, and also some variation associated with the orbital motion.[8]

KQ Puppis B is an eclipsing binary with an orbital period of 17.26 days and an estimated semi-major axis of 0.3 astronomical units. This inner pair orbits the red supergiant with an orbital period of 9,500 days and a semi-major axis of 24.9 au. KQ Puppis Ba is a rapidly-rotating B-type main-sequence star, with a mass between 7.5 and 11.5 times that of the Sun, a luminosity 8,900 times solar and a temperature around 19,900 K. KQ Puppis Bb has a mass in the range of 1.2–8.1 M and is thought to be either an A or F-type main-sequence star. The eccentricity of the inner orbit (≥0.236) is much higher than the expected for such a compact system, suggesting that the stellar wind of the supergiant is exciting the pair's eccentricity. No evidence of past mass transfer between the components has been found.[4]

The red supergiant is losing mass from its strong stellar wind. Some of this mass is being transferred to the secondary (B), forming a disk of material around it.[4] Binaries with such a characteristic are referred to as VV Cephei systems, although in this case the components do not eclipse each other.[9] A portion of the disc does appear to be eclipsed and this is detected as a strong drop in far-ultraviolet radiation for about a third of the orbit.[5]

KQ Puppis has been catalogued as an outlying member of the open cluster Messier 47 (NGC 2422) and would be the brightest member of that cluster.[10] Membership is uncertain as it appears to be more distant than the other stars in the cluster.[11]

References

  1. 1.0 1.1 Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode2007A&A...474..653V. 
  2. 2.0 2.1 2.2 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: 0. Bibcode2002yCat.2237....0D. 
  3. 3.0 3.1 Samus, N. N. et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S 1: 02025. Bibcode2009yCat....102025S. 
  4. 4.00 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 4.11 Jadlovský, D.; Molnár, L.; Ercolino, A.; Bernini-Peron, M.; Mérand, A.; Krtička, J.; Wang, L.; Ádám, R. Z.; Baade, D. (2025-09-29). "Hidden massive eclipsing binaries in red supergiant systems: The hierarchical triple system KQ Puppis and other candidates". arXiv:2509.25168 [astro-ph.SR].
  5. 5.0 5.1 González-Riestra, R.; Rossi, C.; Viotti, R. F. (2003). "First far-UV observations of KQ Puppis with FUSE". Astronomy and Astrophysics 399 (2): 681. doi:10.1051/0004-6361:20021830. Bibcode2003A&A...399..681G. 
  6. 6.0 6.1 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  7. "Hipparcos Tools Interactive Data Access". ESA. https://www.cosmos.esa.int/web/hipparcos/interactive-data-access. 
  8. Viotti, R.; Rossi, C.; Muratorio, G. (1998). "Optical and near-IR observations of variable stars with AURELIE". Astronomy and Astrophysics Supplement 128 (3): 447. doi:10.1051/aas:1998156. Bibcode1998A&AS..128..447V. 
  9. Rossi, C.; Altamore, A.; Baratta, G. B.; Friedjung, M.; Viotti, R. (1992). "The spectrum of the VV Cephei star KQ Puppis (Boss 1985). III - A possible model". Astronomy and Astrophysics 256: 133. Bibcode1992A&A...256..133R. 
  10. Van Schewick, H. (1966). "Untersuchungen uber die Eigenbewegungen von Sternhaufen. XII. NGC 2422, NGC 2423, NGC 7209 und An. Bakhatova I im Sel. Area 40". Veroeff. Univ. Sternw. Bonn 74: 1. Bibcode1966VeBon..74....1V. 
  11. Baumgardt, H.; Dettbarn, C.; Wielen, R. (2000). "Absolute proper motions of open clusters. I. Observational data". Astronomy and Astrophysics Supplement 146 (2): 251. doi:10.1051/aas:2000362. Bibcode2000A&AS..146..251B. 




Licensed under CC BY-SA 3.0 | Source: https://handwiki.org/wiki/Astronomy:KQ_Puppis
15 views |
↧ Download this article as ZWI file
Encyclosphere.org EncycloReader is supported by the EncyclosphereKSF