9 Puppis

9 Puppis
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]
Distance53.8 ± 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
Mass1.061±0.002[4] M☉
Surface gravity (log g)4.21[7] cgs
Temperature5,917±80[7] K
Metallicity [Fe/H]−0.13[7] dex
Rotational velocity (v sin i)6.4±0.1[8] km/s
Age6.83[9] Gyr
B
Mass0.900±0.002[4] M☉
Other designations
9 Pup, BD−13° 2267, GC 10629, GJ 291, HD 64096, HIP 38382, HR 3064, SAO 153500, ADS 6420, WDS J07518-1354, BU 101, 2MASS J07514629-1353526[10]
Database references
SIMBADdata

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]

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]

  1. ^ a b c d e Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference Anderson_Francis_2012 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Gray_et_al_2006 was invoked but never defined (see the help page).
  4. ^ a b c d e Cite error: The named reference Andrade2019 was invoked but never defined (see the help page).
  5. ^ a b c d e Cite error: The named reference Pourbaix2000 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Duquennoy_Mayor_1988 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference Casagrande_et_al_2011 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference AmmlerVonEiff_Reiners_2012 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference Vican2012 was invoked but never defined (see the help page).
  10. ^ a b c Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ a b c Cite error: The named reference Woolley_Symms_1937 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Breakiron_Gatewood_1975 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Heintz1989 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Holman_Wiegert_1999 was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference Jaime_et_al_2012 was invoked but never defined (see the help page).
  16. ^ Cite error: The named reference Dvorak_et_al_1989 was invoked but never defined (see the help page).
  17. ^ Cite error: The named reference Miczaika1954 was invoked but never defined (see the help page).
  18. ^ Cite error: The named reference Soderblom_Mayor_1993 was invoked but never defined (see the help page).