WASP-17
Star in the constellation Scorpius
From Wikipedia, the free encyclopedia
WASP-17, also named Dìwö, is an F-type main sequence star approximately 1,310 light-years away in the constellation Scorpius.[2] It hosts the planet WASP-17b.[4][8]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Scorpius[1] |
| Right ascension | 15h 59m 50.9492s[2] |
| Declination | −28° 03′ 42.313″[2] |
| Apparent magnitude (V) | 11.500[3] |
| Characteristics | |
| Evolutionary stage | main sequence[2] |
| Spectral type | F6V[4] |
| Astrometry | |
| Radial velocity (Rv) | −48.34±1.07[2] km/s |
| Proper motion (μ) | RA: −8.263(29) mas/yr[2] Dec.: −9.427(22) mas/yr[2] |
| Parallax (π) | 2.4811±0.0255 mas[2] |
| Distance | 1,310 ± 10 ly (403 ± 4 pc) |
| Details | |
| Mass | 1.306±0.026[5] M☉ |
| Radius | 1.572±0.056[5] R☉ |
| Surface gravity (log g) | 4.14 ± 0.03[6] cgs |
| Temperature | 6509 ± 86[6] K |
| Metallicity [Fe/H] | –0.02 ± 0.09[6] dex |
| Rotational velocity (v sin i) | 10.6 ± 1.3[6] km/s |
| Age | 2.65±0.25[5] Gyr |
| Other designations | |
| Dìwö, CD−27 10695, TOI-1050, TIC 66818296, WASP-17, TYC 6787-1927-1, 2MASS J15595095-2803422, 1SWASP J155950.94−280342.3[7] | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
The star, although similar to the Sun in terms of overall contents of heavy elements, is depleted of carbon. The carbon to oxygen molar ratio of 0.18±0.04 for WASP-17 is well below the solar ratio of 0.55.[9]
Nomenclature
The planet was discovered by the SuperWASP project, hence the name WASP-17.
This was one of the systems selected to be named in the 2019 NameExoWorlds campaign during the 100th anniversary of the IAU, which assigned each country a star and planet to be named. This system was assigned to Costa Rica. WASP-17 is named Dìwö, which in the Bribri language means the Sun, and its planet is named Ditsö̀.[10][11]
Planetary system
As of 2009, an exoplanet has been confirmed to orbit the star. The planet, WASP-17b, is unusual in that it is believed to orbit in the opposite direction to the star's spin (a retrograde orbit), and is twice the size of Jupiter, but half its mass.[12][13] The planet is also named Ditsö̀. It is subject to intensive photo-evaporation, and may be completely destroyed within one billion years from now.[14]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b / Ditsö̀ | 0.512±0.037 MJ | 0.05151±0.00035 | 3.7354845(19) | <0.020 | 86.83+0.68 −0.53° |
1.991±0.081 RJ |