9 Puppis is a binary star system in the southern constellation of Puppis.[10] It was originally designated 9 Argus,[11] being part of the now defunct Argo Navis constellation. The system is faintly visible to the naked eye as a point of light with a combined apparent visual magnitude of 5.16.[2] The magnitude difference between the two stars is 0.65.[6] Parallax measurements yield a distance estimate to 9 Puppis of approximately 54 light years from the Sun, with the dynamic and trigonometric parallaxes for the system being in close agreement.[4] It is drifting closer with a systemic radial velocity of –21 km/s.[5] The motion of the system through space is predicted to bring it as close as 42.2 light-years in about 292,000 years.[2]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Puppis |
| Right ascension | 07h 51m 46.30295s[1] |
| Declination | −13° 53′ 52.9169″[1] |
| Apparent magnitude (V) | 5.16[2] |
| Characteristics | |
| Spectral type | G0V[3] (G1 + G9)[4] |
| B−V color index | 0.600±0.007[2] |
| Astrometry | |
| Radial velocity (Rv) | −21.34±0.16[5] km/s |
| Proper motion (μ) | RA: −67.75[1] mas/yr Dec.: −346.66[1] mas/yr |
| Parallax (π) | 60.59 ± 0.59 mas[1] |
| Distance | 53.8 ± 0.5 ly (16.5 ± 0.2 pc) |
| Absolute magnitude (MV) | 4.07[2] (4.65 + 5.30)[6] |
| Orbit[5] | |
| Period (P) | 22.7010 ± 0.0270 yr |
| Semi-major axis (a) | 602.0±7.2 mas |
| Eccentricity (e) | 0.741±0.007 |
| Inclination (i) | 80.4±0.21° |
| Longitude of the node (Ω) | 102.9±0.27° |
| Periastron epoch (T) | 1,985.92±0.021 Byr |
| Argument of periastron (ω) (secondary) | 73.1±0.4° |
| Semi-amplitude (K1) (primary) | 9.12±0.63 km/s |
| Semi-amplitude (K2) (secondary) | 9.69±0.26 km/s |
| Details | |
| A | |
| Mass | 1.061±0.002[4] M☉ |
| Surface gravity (log g) | 4.21[7] cgs |
| Temperature | 5,917±80[7] K |
| Metallicity [Fe/H] | −0.13[7] dex |
| Rotational velocity (v sin i) | 6.4±0.1[8] km/s |
| Age | 6.83[9] Gyr |
| B | |
| Mass | 0.900±0.002[4] M☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
The binary nature of this system was discovered by S. W. Burnham in 1873,[12] and it now has the discovery code BU 101[10] (originally: β 101[11]). Early efforts at computing orbital elements were made by Burnham (1894), Aitken (1914), and others.[11] The latest refined elements show an orbital period of 22.7 years with a large eccentricity (ovalness) of 0.74.[5] The orbital plane is highly inclined to the line of sight[13] at an angle of 80.4°.[5]
The physical size of the system's semimajor axis is estimated to be 10 AU. The large eccentricity of their orbit means a circumstellar planetary orbit would most likely only be stable over long periods with a semimajor axis inside 0.67 AU from the primary and 0.63 AU from the secondary.[14] An outer circumbinary planet would have a stable orbit with a semimajor axis beyond about 34.5 AU from the barycenter.[15][16]
The stellar classification of the 9 Puppis system is G0V,[3] matching a G-type main-sequence star like the Sun. The dynamic masses of the components are 1.06 and 0.90 times the mass of the Sun, yielding estimated individual stellar classes of G1 for the primary and G9 for the secondary, respectively.[4] The system has been listed as a probable member of the Ursa Major Moving Group,[17] but was excluded by Soderblom and Mayor (1993) due to low lithium abundance and low X-ray flux.[18] Their age determined from chromospheric heating is around seven billion years.[9]
References
edit- ^ a b c d e van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
- ^ a b c d e Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
- ^ a b Gray, R. O.; et al. (July 2006). "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc—The Southern Sample". The Astronomical Journal. 132 (1): 161–170. arXiv:astro-ph/0603770. Bibcode:2006AJ....132..161G. doi:10.1086/504637. S2CID 119476992.
- ^ a b c d e Andrade, Manuel (October 2019). "Colour-dependent accurate modelling of dynamical parallaxes and masses of visual binaries. Application to the VB+SB2 systems with definitive orbits". Astronomy & Astrophysics. 630: 11. Bibcode:2019A&A...630A..96A. doi:10.1051/0004-6361/201936199. A96.
- ^ a b c d e Pourbaix, D. (2000), "Resolved double-lined spectroscopic binaries: A neglected source of hypothesis-free parallaxes and stellar masses", Astronomy and Astrophysics Supplement Series, 145 (2): 215–222, Bibcode:2000A&AS..145..215P, doi:10.1051/aas:2000237.
- ^ a b Duquennoy, A.; Mayor, M. (1988). "Duplicity in the solar neighbourhood. III: New spectroscopic elements for nine solar-type binary stars". Astronomy and Astrophysics. 195: 129–147. Bibcode:1988A&A...195..129D.
- ^ a b c Casagrande, L.; et al. (June 2011). "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey". Astronomy and Astrophysics. 530: A138. arXiv:1103.4651. Bibcode:2011A&A...530A.138C. doi:10.1051/0004-6361/201016276. S2CID 56118016.
- ^ Ammler-von Eiff, Matthias; Reiners, Ansgar (June 2012), "New measurements of rotation and differential rotation in A-F stars: are there two populations of differentially rotating stars?", Astronomy & Astrophysics, 542: A116, arXiv:1204.2459, Bibcode:2012A&A...542A.116A, doi:10.1051/0004-6361/201118724, S2CID 53666672.
- ^ a b Vican, Laura (June 2012). "Age Determination for 346 Nearby Stars in the Herschel DEBRIS Survey". The Astronomical Journal. 143 (6): 135. arXiv:1203.1966. Bibcode:2012AJ....143..135V. doi:10.1088/0004-6256/143/6/135. S2CID 118539505.
- ^ a b c "9 Pup". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-04-14.
- ^ a b c Woolley, R. d. v. R.; Symms, L. S. T. (April 1937). "Two visual binary orbits". Monthly Notices of the Royal Astronomical Society. 97 (6): 438–453. Bibcode:1937MNRAS..97..438W. doi:10.1093/mnras/97.6.438.
- ^ Breakiron, L. A.; Gatewood, G. (April 1975). "Parallax, mass, and orbit of the 9 Puppis binary system". Astronomical Journal. 80: 318–320. Bibcode:1975AJ.....80..318B. doi:10.1086/111748.
- ^ Heintz, W. D. (May 1989). "The Orbits of MU Orionis and 9 Puppis". Publications of the Astronomical Society of the Pacific. 101: 510. Bibcode:1989PASP..101..510H. doi:10.1086/132460. S2CID 120926260.
- ^ Holman, Matthew J.; Wiegert, Paul A. (January 1999). "Long-Term Stability of Planets in Binary Systems". The Astronomical Journal. 117 (1): 621–628. arXiv:astro-ph/9809315. Bibcode:1999AJ....117..621H. doi:10.1086/300695. S2CID 291029.
- ^ Jaime, Luisa G.; et al. (December 2012). "Regions of dynamical stability for discs and planets in binary stars of the solar neighbourhood". Monthly Notices of the Royal Astronomical Society. 427 (4): 2723–2733. arXiv:1208.2051. Bibcode:2012MNRAS.427.2723J. doi:10.1111/j.1365-2966.2012.21839.x. S2CID 118570249.
- ^ Dvorak, R.; et al. (December 1989). "Stability of outer planetary orbits (P-types) in binaries". Astronomy and Astrophysics. 226: 335−342. Bibcode:1989A&A...226..335D.
- ^ Miczaika, G. R. (1954). "The color-luminosity diagram of the Ursa Major group". Astronomical Journal. 59: 233–240. Bibcode:1954AJ.....59..233M. doi:10.1086/107003.
- ^ Soderblom, David R.; Mayor, Michel (January 1993). "Stellar Kinematic Groups. I. The URSA Major Group". Astronomical Journal. 105: 226. Bibcode:1993AJ....105..226S. doi:10.1086/116422.