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 Eclipsing binary

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.[3] 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.[4]

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,[5] 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).[6]

References

  1. 1.0 1.1 SIMBAD, TV Pic -- Ellipsoidal variable Star (accessed 25 May 2014)
  2. 2.0 2.1 2.2 Otero, Sebastian Alberto (21 November 2012). "TV Pictoris". AAVSO Website. American Association of Variable Star Observers. Retrieved 25 May 2014.
  3. 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.
  4. 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.
  5. 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.Vizier catalog entry
  6. 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. arXiv:0807.4989. Bibcode:2009AN....330...68E. doi:10.1002/asna.200811041.