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 2 SIMBAD, TV Pic -- Ellipsoidal variable Star (accessed 25 May 2014)
- 1 2 3 Otero, Sebastian Alberto (21 November 2012). "TV Pictoris". AAVSO Website. American Association of Variable Star Observers. Retrieved 25 May 2014.
- ↑ 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.
- ↑ 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.
- ↑ 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.
- ↑ 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 - ↑ 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.