OY Carinae (abbreviated OY Car) is an eclipsing binary system approximately 277 light-years away from the Sun, classed as a cataclysmic variable. The system comprises an eclipsing white dwarf and red dwarf that orbit each other every 1.51 hours, and possibly a yet unconfirmed third low-mass (substellar?) companion.
 A blue band light curve for OY Carinae, adapted from Khruzina1 et al. (2003).[1] The main plot shows the full light curve, and the inset shows the minimum with an expanded horizontal scale. | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Carina |
| Right ascension | 10h 06m 22.07s |
| Declination | −70° 14′ 04.6″ |
| Apparent magnitude (V) | +12.2 |
| Characteristics | |
| Spectral type | DA / M6V |
| Astrometry | |
| Radial velocity (Rv) | 120 km/s |
| Distance | 277.1 ly (85[2] pc) |
| Details | |
| Mass | ≈0.7[2]/0.07[3] M☉ |
| Radius | 0.011[2]/0.127[3] R☉ |
| Luminosity | 0.0055/0.00117 L☉ |
| Temperature | 15,000/3,000 K |
| Orbit | |
| Period (P) | 0.000172 yr |
| Semi-major axis (a) | 0.00213 AU |
| Eccentricity (e) | 0.0 |
| Inclination (i) | 83.3° |
| Other designations | |
OY Car, RX J1006.5-7014, SON 6302, 2MASS J10062206-7014045, SBC9 600, AAVSO 1004-69 | |
| Database references | |
| SIMBAD | data |
Planetary system?
editGreenhill et al. (2009) would invoke the presence of a third object to explain orbital period variations with an apparent periodicity of roughly 35 years. The third body could yield a minimum mass 7 times greater than Jupiter and be located 9.5 astronomical units away from the cataclysmic variable system,[4] being likely either a massive planetary object or else a very low-mass brown dwarf. It is likely that the apparent change is due to solar cycle type magnetic activity in the secondary star. Large irregular deviations from the general trend, with time-scales of years, also occur. Further observations will be able to confirm or disprove the presence of a substellar companion.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (years) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b (unconfirmed) | ≥7 MJ | 9.5 | 35±3.5 | ? | — | — |
See also
editReferences
edit- ^ Khruzina, T. S.; Cherepashchuk, A. M.; Bisikalo, D. V..; Boyarchuk, A. A.; Kuznetsov, O. A. (March 2003). "Interpretation of Light Curves of the Cataclysmic Variable OY Car in a Model with Shockless Interaction between a Gaseous Stream and the Disk". Astronomy Reports. 47 (3): 214–231. Bibcode:2003ARep...47..214K. doi:10.1134/1.1562216. S2CID 119896879. Retrieved 19 November 2021.
- ^ a b c Mauche & Raymond (2000). "The EUV Emission-Line spectrum of OY Carinae in superoutburst: scattering in the wind" (PDF). Revista Mexicana de Astronomía y Astrofísica, Serie de Conferencias. 9: 232–233. Bibcode:2000RMxAC...9..232M.
- ^ a b Wood; Horne, Keith; Berriman, Graham; Wade, Richard A. (1989). "Eclipse studies of the dwarf nova OY Carinae in quiescence". Astrophysical Journal. 341: 974–994. Bibcode:1989ApJ...341..974W. doi:10.1086/167557.
- ^ a b Greenhill; Hill, K. M.; Dieters, S.; Fienberg, K.; et al. (2006). "Decrease in the orbital period of dwarf nova OY Carinae". Monthly Notices of the Royal Astronomical Society. 372 (3): 1129–1132. arXiv:astro-ph/0602331. Bibcode:2006MNRAS.372.1129G. doi:10.1111/j.1365-2966.2006.10920.x. S2CID 15940077.