WASP-12
Star in the constellation Auriga
From Wikipedia, the free encyclopedia
WASP-12 is a magnitude 11 yellow dwarf star located approximately 1347 light-years away[2] in the constellation Auriga.[6] WASP-12 has a mass and radius similar to the Sun and is known for being orbited by a planet that is extremely hot and has a retrograde orbit around WASP-12. WASP-12 forms a triple star system with two red dwarf companions. Both of them have spectral types of M3V and are only 38% and 37% as massive as the Sun, respectively.[5]
WASP-12A (left) with WASP-12B and C (right, indicated) taken from Keck AO | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Auriga[1] |
| Right ascension | 06h 30m 32.7966s[2] |
| Declination | +29° 40′ 20.264″[2] |
| Apparent magnitude (V) | 11.560±0.068[3] |
| Characteristics | |
| Spectral type | G0V[4] + M3V + M3V[5] |
| Apparent magnitude (B) | 12.138±0.019[3] |
| Apparent magnitude (R) | ~11.6[6] |
| Apparent magnitude (J) | 10.477±0.021[7] |
| Apparent magnitude (H) | 10.228±0.022[7] |
| Apparent magnitude (K) | 10.188±0.020[7] |
| Astrometry | |
| Radial velocity (Rv) | 20.62±1.44[2] km/s |
| Proper motion (μ) | RA: −1.519(19) mas/yr[2] Dec.: −6.761(15) mas/yr[2] |
| Parallax (π) | 2.4213±0.0166 mas[2] |
| Distance | 1,347 ± 9 ly (413 ± 3 pc) |
| Orbit[5] | |
| Primary | WASP-12 A |
| Name | WASP-12 BC |
| Period (P) | 393.9 days |
| Semi-major axis (a) | 21±3 AU |
| Details | |
| A | |
| Mass | 1.325+0.026 −0.018[8] M☉ |
| Radius | 1.690+0.019 −0.018[8] R☉ |
| Luminosity | 4.05+0.54 −0.53[9] L☉ |
| Surface gravity (log g) | 4.11±0.11[8] cgs |
| Temperature | 6265±50[8] K |
| Metallicity [Fe/H] | +0.12±0.07[8] dex |
| Rotational velocity (v sin i) | <1.9[8] km/s |
| Age | 3.05±0.32[8] Gyr |
| Details | |
| B | |
| Mass | 0.38±0.05[5] M☉ |
| C | |
| Mass | 0.37±0.05[5] M☉ |
| Other designations | |
| TOI-1725, TIC 86396382, TYC 1891-1178-1, 2MASS J06303279+2940202, UCAC2 42216354[6] | |
| Database references | |
| SIMBAD | A |
| BC | |
| Exoplanet Archive | data |
Planetary system
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In 2008, the exoplanet WASP-12b was discovered orbiting WASP-12 by SuperWASP, using the transit method. It is a hot Jupiter completing an orbit around its star in just one day.[10] Its high carbon-to-oxygen ratio indicates that rocky planets might have formed in the star system, and it may be a carbon planet.[11] It is subject to intensive photo-evaporation, and may be completely destroyed within one billion years from now.[12]
In 2015, no indications of additional planets were found in the WASP-12 system.[9]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 1.465±0.079 MJ | 0.0232±0.00064 | 1.09142030(14)[9] | <0.02[14] | 83.52±0.03° | 1.937±0.056 RJ |