DQ Herculis
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This article refers to Nova Herculis 1934. Information on the star DQ Herculis is also here. For the type of cataclysmic variable star known as DQ Herc, see intermediate polars
|
DQ Herculis |
|
| Observation data Epoch J2000 Equinox J2000 |
|
|---|---|
| Constellation | Hercules |
| Right ascension | 18h 07m 30.25s |
| Declination | +45° 51′ 32.6″ |
| Apparent magnitude (V) | 15.16 |
| Characteristics | |
| Spectral type | DBe+M2V |
| Variable type | DQ Herculis |
| Astrometry | |
| Radial velocity (Rv) | -4 km/s |
| Parallax (π) | -5 ± 11 mas |
| Distance | 316.2 ly (97 pc) |
| Absolute magnitude (MV) | 12.99 |
| Details | |
| Mass | 0.7/0.4 M☉ |
| Radius | 0.012/0.44 R☉ |
| Luminosity | 0.0064/0.03 L☉ |
| Temperature | 14,500/3,500 K |
| Orbit | |
| Period (P) | 0.0002 yr |
| Semimajor axis (a) | 0.003 Astronomical Units" |
| Inclination (i) | 81.7° |
| Other designations | |
| Database references | |
| SIMBAD | data |
DQ Herculis (or Nova Herculis 1934) was a slow, bright nova occurring in Hercules in December 1934. It reached magnitude 1.5.
DQ Herculis is the prototype for a category of cataclysmic variable stars called intermediate polars. The system shows orbital period variation, likely due to the presence of a third body[1].
Substellar companion [edit]
Dai & Qian (2009) invoke the presence of a third object to explain orbital period variations observed in the dwarf nova. If the third body is confirmed, it would likely turn out a brown dwarf companion.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (years) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b (unconfirmed) | ≥20 MJ | 6.5 | 17.7 | ≤0.12 | — | — |
References [edit]
- ^ a b Dai & Qian; Qian, S. B. (2009). "Plausible explanations for the variations of orbital period in the old nova DQ Herculis". Astronomy and Astrophysics 503 (3): 883–888. Bibcode:2009A&A...503..883D. doi:10.1051/0004-6361/200810909.
External links [edit]
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