WASP-2
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Delphinus |
| A | |
| Right ascension | 20h 30m 54.1282s |
| Declination | +06° 25′ 46.341″ |
| Apparent magnitude (V) | +11.98 |
| C | |
| Right ascension | ~20h 30m 54s |
| Declination | ~+06° 25′ 46″ |
| Characteristics | |
| Spectral type | K1.5V + K2-M3 |
| Apparent magnitude (J) | 10.166±0.027 |
| Apparent magnitude (H) | 9.752±0.026 |
| Apparent magnitude (K) | 9.632±0.024 |
| Variable type | planetary transit |
| Astrometry | |
| Radial velocity (Rv) | −27.70±0.46 km/s |
| Proper motion (μ) | RA: 5.631 mas/yr Dec.: −48.491 mas/yr |
| Parallax (π) | 6.5777±0.0270 mas |
| Distance | 496 ± 2 ly (152.0 ± 0.6 pc) |
| Orbit | |
| Primary | WASP-2A |
| Companion | WASP-2B |
| Semi-major axis (a) | 106″ |
| Details | |
| WASP-2A | |
| Mass | 0.843±0.033 M☉ |
| Radius | 0.821±0.013 R☉ |
| Luminosity | 0.507+0.023 −0.029 L☉ |
| Surface gravity (log g) | 4.536±0.015 cgs |
| Temperature | 5170±60 K |
| Metallicity [Fe/H] | 0.1±0.2 dex |
| Rotational velocity (v sin i) | 0.9±0.5 km/s |
| Age | 7.6+2.5 −3.3 Gyr |
| WASP-2B | |
| Mass | 0.40±0.02 M☉ |
| Temperature | 3523+28 −19 K |
| Other designations | |
| V357 Del, TOI-5797, TIC 374530847, WASP-2, GSC 00522-01199, 2MASS J20305413+0625463, 1SWASP J203054.12+062546.4, USNO-B1.0 0964-00543604, UCAC2 34018636 | |
| Database references | |
| SIMBAD | A |
| B | |
| Exoplanet Archive | data |
WASP-2 is a binary star system located about 496 light-years away in the Delphinus constellation. The primary is a magnitude 12 orange dwarf star, orbited by a red dwarf star on a wide orbit. The star system shows an infrared excess noise of unknown origin.
The primary star hosts one known exoplanet, WASP-2b. Since the planet transits the star, the star is classified as a planetary transit variable and has received the variable star designation V357 Delphini.