TV Pictoris

TV Pictoris
Observation data
Epoch J2000      Equinox J2000
Constellation Pictor
Right ascension 04h 48m 57.47286s[1]
Declination −47° 08′ 04.2557″[1]
Apparent magnitude (V) 7.37 - 7.53[2]
Characteristics
Spectral type A2V[2]
Variable type Ellipsoidal[3]

TV Pictoris is a rotating ellipsoidal variable star in the constellation Pictor. It ranges between apparent magnitude 7.37 - 7.53 over a period of 0.85 days.[2] It was first discovered to be variable in 1987.[4] The system is inclined at an angle of 54 degrees to observers on Earth. It is composed of a primary star that has a radius 4.3 times that of the sun and 1.2 times its mass, and an effective (surface) temperature of 8300 K, and a secondary star with a radius 2.1 times that of the sun and 40% of its mass, and an effective temperature of 7000 K. Both stars are less massive than expected for a main sequence star of their temperatures. The secondary rotates much faster than the primary.[5]

The system shines with a combined spectrum of A2V. Based upon an annual parallax shift of 5.14 milliarc seconds as measured by the Hipparcos satellite,[6] this system is 640 light-years (195 parsecs) from Earth. Analysing and recalibrating yields a parallax of 4.70 and hence a distance of 690 light-years (213 parsecs).[7]

References

  1. 1 2 SIMBAD, TV Pic -- Ellipsoidal variable Star (accessed 25 May 2014)
  2. 1 2 3 Otero, Sebastian Alberto (21 November 2012). "TV Pictoris". AAVSO Website. American Association of Variable Star Observers. Retrieved 25 May 2014.
  3. ↑ Samus, N. N.; Durlevich, O. V.; 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. Bibcode:2009yCat....102025S.
  4. ↑ Verschuren, W.; Hensberge, H.; Schneider, H.; Pavlovski, K. (1987). "HD 30861, a New Ellipsoidal Variable". Information Bulletin on Variable Stars. 3120. Bibcode:1987IBVS.3120....1V.
  5. ↑ Pavlovski, K.; Cuypers, J.; David, M.; Griffin, R. E. M.; et al. (1998). "The nearby ellipsoidal variable TV Pictoris". Astronomy and Astrophysics. 331: 639–50. Bibcode:1998A&A...331..639P.
  6. ↑ van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. Bibcode:2007A&A...474..653V. arXiv:0708.1752 Freely accessible. doi:10.1051/0004-6361:20078357.Vizier catalog entry
  7. ↑ Eker, Z.; Bilir, S.; Yaz, E.; Demircan, O.; et al. (2009). "New absolute magnitude calibrations for W Ursa Majoris type binaries". Astronomische Nachrichten. 330 (1): 68–77. Bibcode:2009AN....330...68E. arXiv:0807.4989 Freely accessible. doi:10.1002/asna.200811041.
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