WASP-4
WASP-4 is a G-type main-sequence star approximately 891 light-years away in the constellation of Phoenix.[1][2][4] Despite its advanced age, the star is rotating rapidly, being spun up by the tides raised by a giant planet on a close orbit.[8]
Planetary system
In 2007 the exoplanet WASP-4b was discovered orbiting this star. With an orbital period of just 1.3 days, it is classified as a hot Jupiter.[4] The planet's orbital period appears to be decreasing at a rate of 7.33±0.71 milliseconds per year, suggesting that its orbit is decaying, with a decay timescale of 15.77±1.57 million years.[9] Another superjovian planet in the system has been suspected.[9] A 2025 study further supported orbital decay for WASP-4b,[5] but another same-year study discounted this, attributing all evidence for orbital decay to the light travel time effect of an outer planet.[10] Although the previous candidate has not been addressed, this planet has nearly the same orbital elements and thus both should be the same object.[10]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination (°) |
Radius |
|---|---|---|---|---|---|---|
| b[5] | 1.200+0.032 −0.030 MJ |
0.02294+0.00028 −0.00026 |
1.338230994(84) | 0.0013+0.0005 −0.0009 |
88.05+0.85 −0.53 |
1.349+0.011 −0.012 RJ |
| c[10] | ≥6.93+1.10 −0.47 MJ |
7.96+0.72 −0.32 |
8,650+1,200 −510 |
— | — | — |
See also
References
- ^ a b Template:Cite constellation
- ^ a b c d e f g Template:Cite Gaia DR3
- ^ a b c Page Module:Citation/CS1/styles.css has no content.Henden, A. A.; et al. (2016). "VizieR Online Data Catalog: AAVSO Photometric All Sky Survey (APASS) DR9 (Henden+, 2016)". VizieR On-line Data Catalog: II/336. Originally Published in: 2015AAS...22533616H. 2336. Bibcode:2016yCat.2336....0H. Vizier catalog entry Script error: No such module "webarchive".
- ^ a b c d Page Module:Citation/CS1/styles.css has no content.Wilson, D. M.; et al. (2008). "WASP-4b: A 12th Magnitude Transiting Hot Jupiter in the Southern Hemisphere". The Astrophysical Journal Letters. 675 (2): L113–L116. arXiv:0801.1509. Bibcode:2008ApJ...675L.113W. doi:10.1086/586735. S2CID 10823235.
- ^ a b c d e f Page Module:Citation/CS1/styles.css has no content.Baştürk, Ö; Kutluay, A. C.; Barker, A.; Yalçınkaya, S.; Southworth, J.; Barkaoui, K.; Wünsche, A.; Burgdorf, M. J.; Timmermans, M. (2025-06-17). "The Orbit of WASP-4 b is in Decay". Monthly Notices of the Royal Astronomical Society. 541 (2): 714–730. arXiv:2506.15022. doi:10.1093/mnras/staf1009.
- ^ a b c d Page Module:Citation/CS1/styles.css has no content.Bonomo, A. S.; Desidera, S.; et al. (June 2017). "The GAPS Programme with HARPS-N at TNG. XIV. Investigating giant planet migration history via improved eccentricity and mass determination for 231 transiting planets". Astronomy & Astrophysics. 602: A107. arXiv:1704.00373. Bibcode:2017A&A...602A.107B. doi:10.1051/0004-6361/201629882.
- ^ Page Module:Citation/CS1/styles.css has no content."WASP-4". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-09-22.
{{cite web}}: Invalid|mode=Script error: No such module "Citation mode".(help) - ^ Page Module:Citation/CS1/styles.css has no content.Maxted, P. F. L.; Serenelli, A. M.; Southworth, J. (2015), "A comparison of gyrochronological and isochronal age estimates for transiting exoplanet host stars", Astronomy & Astrophysics, 577: A90, arXiv:1503.09111, Bibcode:2015A&A...577A..90M, doi:10.1051/0004-6361/201525774, S2CID 53324330
- ^ a b Page Module:Citation/CS1/styles.css has no content.Turner, Jake D.; Flagg, Laura; Ridden-Harper, Andrew; Jayawardhana, Ray (2022), "Characterizing the WASP-4 System with TESS and Radial Velocity Data: Constraints on the Cause of the Hot Jupiter's Changing Orbit and Evidence of an Outer Planet", The Astronomical Journal, 163 (6): 281, arXiv:2112.09621, Bibcode:2022AJ....163..281T, doi:10.3847/1538-3881/ac686f, S2CID 245329747
- ^ a b c Page Module:Citation/CS1/styles.css has no content.Winn, Joshua N.; Stefánsson, Guđmundur (2025-12-01). "Orbital Decay Candidates Reconsidered: WASP-4 b Is Not Decaying and Kepler-1658 b Is Not a Planet". The Planetary Science Journal. 6 (12): 300. arXiv:2510.05229. doi:10.3847/PSJ/ae21db. ISSN 2632-3338.
External links
- Page Module:Citation/CS1/styles.css has no content."SuperWASP Homepage". Archived from the original on 2002-12-08. Retrieved 2008-07-02.
- Page Module:Citation/CS1/styles.css has no content."UK planet hunters announce three new finds" (PDF). 2007-10-30. Archived from the original (PDF) on 2008-05-16. Retrieved 2008-07-02.
