Rho Puppis

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ρ Puppis
Puppis constellation map.svg
Red circle.svg
Location of ρ Puppis (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Puppis
Right ascension 08h 07m 32.64882s[1]
Declination −24° 18′ 15.5679″[1]
Apparent magnitude (V) 2.78[2]
Characteristics
Spectral type F5IIkF2IImF5II[3]
U−B color index +0.17[2]
B−V color index +0.40[2]
Variable type δ Sct[4]
Astrometry
Radial velocity (Rv) +46.1[5] km/s
Proper motion (μ) RA: –83.35[1] mas/yr
Dec.: +46.23[1] mas/yr
Parallax (π) 51.33 ± 0.15[1] mas
Distance 63.5 ± 0.2 ly
(19.48 ± 0.06 pc)
Absolute magnitude (MV) 1.41[6]
Details
Mass 1.85[7] M
Radius 3.41[8] R
Luminosity 22[7] L
Surface gravity (log g) 3.70[9] cgs
Temperature 6,920[10] K
Metallicity [Fe/H] 0.35[9] dex
Rotational velocity (v sin i) 15[11] km/s
Age 2[12] Gyr
Other designations
ρ Puppis, 15 Puppis, CPD−23° 3368, FK5 308, HD 67523, HIP 39757, HR 3185, SAO 175217.[13]
Database references
SIMBAD data

Rho Puppis (ρ Puppis, abbreviated Rho Pup, ρ Pup), also named Tureis,[14] is a star in the southern constellation of Puppis. With an average apparent visual magnitude of 2.78,[2] it is the third-brightest member of this generally faint constellation. Based upon parallax measurements made during the Hipparcos mission, Rho Puppis is located at a distance of 63.5 light-years (19.5 parsecs) from the Sun.[1] It is the prototype of the ρ Puppis class of evolved Am stars.

Nomenclature[edit]

ρ Puppis (Latinised to Rho Puppis) is the star's Bayer designation.

It bore the traditional name Tureis or Turais, which was shared by Iota Carinae;[15] in 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)[16] to catalogue and standardize proper names for stars. The WGSN approved the name Tureis for this star on 12 September 2016 and it is now so entered in the IAU Catalog of Star Names (Iota Carinae was given the name Aspidiske on 20 July 2016).[14]

Properties[edit]

At present Rho Puppis is moving away from the Sun with a radial velocity of +46.1 km s−1. The closest approach occurred about 394,000 years ago when it came within roughly 11.6 ly (3.6 pc) of the Solar System; about the same distance as Procyon in the present era.[17]

The variability of this star was announced in 1956 by American astronomer Olin J. Eggen.[4] It was determined to be a Delta Scuti-type variable star, making it one of the first stars of that type to be identified. Photometric observations dating back to 1946 provide a lengthy record of its pattern of pulsation; it undergoes periodic pulsations with a single period of 0.14088143(3) days,[18] or 7.1 cycles per day. During each cycle, the star's magnitude varies with an amplitude of 0.15 and the radial velocity varies by 10 km s−1. The peak brightness occurs 28.8 minutes following the minimum radial velocity.[4] The outer atmosphere's effective temperature of 6,920 K[10] is one of the lowest known for a Delta Scuti variable.[4]

Rho Puppis has an estimated age of about 2 billion years[12] and it has 3.4[8] times the Sun's radius. It has a stellar classification of F5IIkF2IImF5II,[3] this complex format indicates that ρ Puppis is an Am star, with relatively weak lines of calcium and strong lines of other metals. The spectral type indicated by the calcium k line is F5, while that indicated by heavier metal absorption lines is F2, the roman numerals indicate a luminosity class of bright giant. Most such stars are found in binary star systems,[19] but this appears to be an exception as no companion has been discovered.[12][20] Evolved stars with Am-like peculiarities of abundance have come to be known as ρ Puppis stars,[21] the star's metallicity is more than double that in the Sun.[9]

This star shows an excess emission of infrared radiation, suggesting that there is a circumstellar disk of dust orbiting this star. The mean temperature of the emission is 85 K, corresponding to an orbital separation from the host star of 50 AU.[8][12]

References[edit]

  1. ^ a b c d e f van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752Freely accessible, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357 
  2. ^ a b c d Bookmeyer, B. B.; et al. (August 1977), "Photoelectric UBV observations of RR Lyrae variable stars. Second list", Revista Mexicana de Astronomia y Astrofisica, 2: 235–258, Bibcode:1977RMxAA...2..235B 
  3. ^ a b Gray, R. O; Corbally, C. J; Garrison, R. F; McFadden, M. T; Robinson, P. E (2003). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 Parsecs: The Northern Sample. I". The Astronomical Journal. 126 (4): 2048. arXiv:astro-ph/0308182Freely accessible. Bibcode:2003AJ....126.2048G. doi:10.1086/378365. 
  4. ^ a b c d Mathias, P.; et al. (November 1997), "A spectroscopic study of the delta Scuti star rho Puppis", Astronomy and Astrophysics, 327: 1077–1086, Bibcode:1997A&A...327.1077M 
  5. ^ Evans, D. S. (June 20–24, 1966). "The Revision of the General Catalogue of Radial Velocities". In Batten, Alan Henry; Heard, John Frederick. Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30. Determination of Radial Velocities and their Applications. 30. University of Toronto: International Astronomical Union. p. 57. Bibcode:1967IAUS...30...57E. 
  6. ^ Ammler-von Eiff, M.; Reiners, A. (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:1204.2459Freely accessible, Bibcode:2012A&A...542A.116A, doi:10.1051/0004-6361/201118724. 
  7. ^ a b Kaler, James B. (September 5, 2008), "TUREIS (Rho Puppis)", Stars, University of Illinois, retrieved 2012-02-25 
  8. ^ a b c Rhee, Joseph H.; et al. (May 2007), "Characterization of Dusty Debris Disks: The IRAS and Hipparcos Catalogs", The Astrophysical Journal, 660 (2): 1556–1571, arXiv:astro-ph/0609555Freely accessible, Bibcode:2007ApJ...660.1556R, doi:10.1086/509912 
  9. ^ a b c Burkhart, C.; Coupry, M. F. (September 1991), "The A and Am-Fm stars. I - The abundances of Li, Al, Si, and Fe", Astronomy and Astrophysics, 249 (1): 205–216, Bibcode:1991A&A...249..205B 
  10. ^ a b Burkhart, C.; et al. (January 2005), "The field Am and ρ Puppis-like stars: Lithium and heavier elements", Astronomy and Astrophysics, 429 (3): 1043–1049, Bibcode:2005A&A...429.1043B, doi:10.1051/0004-6361:20040467 
  11. ^ Bernacca, P. L.; Perinotto, M. (1970). "A catalogue of stellar rotational velocities". Contributi Osservatorio Astronomico di Padova in Asiago. 239 (1). Bibcode:1970CoAsi.239....1B. 
  12. ^ a b c d Rodriguez, David R.; Zuckerman, B. (February 2012), "Binaries among Debris Disk Stars", The Astrophysical Journal, 745 (2): 147, arXiv:1111.5618Freely accessible, Bibcode:2012ApJ...745..147R, doi:10.1088/0004-637X/745/2/147 
  13. ^ "rho Pup". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-01-25. 
  14. ^ a b "IAU Catalog of Star Names". Retrieved 28 July 2016. 
  15. ^ Moore, Patrick (2005), The observer's year: 366 nights of the universe, Practical Astronomy (2nd ed.), Springer, p. 346, ISBN 1-85233-884-9 
  16. ^ IAU Working Group on Star Names (WGSN), International Astronomical Union, retrieved 22 May 2016. 
  17. ^ García-Sánchez, J.; et al. (November 2001), "Stellar encounters with the solar system", Astronomy and Astrophysics, 379 (2): 634–659, Bibcode:2001A&A...379..634G, doi:10.1051/0004-6361:20011330 
  18. ^ Moon, T.; van Antwerpen, C. (June 2009), "Period Changes in δ Scuti Stars: ρ Puppis", The Journal of the American Association of Variable Star Observers, 37 (1): 3–14, Bibcode:2009JAVSO..37....3M 
  19. ^ Netopil, M.; et al. (November 2008), "Chemically peculiar stars and their temperature calibration", Astronomy and Astrophysics, 491 (2): 545–554, arXiv:0809.5131Freely accessible, Bibcode:2008A&A...491..545N, doi:10.1051/0004-6361:200810325 
  20. ^ Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869–879. arXiv:0806.2878Freely accessible. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. 
  21. ^ Neiner, C; Wade, G. A; Sikora, J (2017). "Discovery of a magnetic field in the δ Scuti F2m star ρ Pup". Monthly Notices of the Royal Astronomical Society: Letters. 468: L46. arXiv:1702.01621Freely accessible. Bibcode:2017MNRAS.468L..46N. doi:10.1093/mnrasl/slx023.