Astronomy:WASP-74
WASP-74 is a star in the constellation of Aquila, located approximately 488 light-years (149 parsecs) from the Sun.[1] At least one exoplanet is known to orbit the star.
Stellar characteristics
WASP-74 is a yellow-white subgiant of spectral type F9. Its apparent magnitude is 9.75, making it invisible to the naked eye. Based on spectroscopic analysis with the HARPS-N spectrograph and Bayesian modelling using PARSEC isochrones, the star has a mass of 1.236 ± 0.026 solar masses, a radius of 1.444±0.044 solar radii, and an effective temperature of 5,883±57 K. Its metallicity ([Fe/H]) is +0.38±0.03, indicating it is notably more metal-rich than the Sun. Stellar models give an age of 3.49±0.65 billion years, and the star's projected rotational velocity is 5.85±0.50 km/s.[2]
The star's proper motion is 1.350±0.082 mas/yr in right ascension and −64.604±0.060 mas/yr in declination, with a radial velocity of −15.32±0.27 km/s.[1]
Planetary system
In 2015, one exoplanet was announced orbiting WASP-74, designated WASP-74 b, discovered by the SuperWASP survey using the transit method.[3] It is a hot Jupiter with a mass of 0.72 Jupiter masses and a radius of 1.312 Jupiter radii, completing one orbit every 2.13775138 days at a distance of 0.0334 astronomical unit|AU from its host star, with an equilibrium temperature of approximately 1,865 K. The planet's orbit is circular and well-aligned with the stellar equator, with a measured sky-projected spin-orbit angle of 0.77±0.99 degrees.[2]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 0.72 MJ | 0.0334 | 2.13775138 | 0 | — | 1.312 RJ |
References
- ↑ 1.0 1.1 "WASP-74". NASA Exoplanet Archive. https://exoplanetarchive.ipac.caltech.edu/overview/WASP-74.
- ↑ 2.0 2.1 Luque, R. (2020). "Obliquity measurement and atmospheric characterisation of the WASP-74 planetary system". Astronomy & Astrophysics 642: A50. doi:10.1051/0004-6361/202038703. Bibcode: 2020A&A...642A..50L.
- ↑ Hellier, C. (2015). "Three WASP-South Transiting Exoplanets: WASP-74b, WASP-83b, and WASP-89b". The Astronomical Journal 150 (1): 18. doi:10.1088/0004-6256/150/1/18. Bibcode: 2015AJ....150...18H.
