WASP-4b

Extrasolar planet in the constellation Phoenix

WASP-4b is an exoplanet, specifically a hot Jupiter, approximately 891 light-years away^[5] in the constellation of Phoenix.^[6]

Discovery

The planet was the discovered by the Wide Angle Search for Planets team using images taken with the SuperWASP-South project's eight wide-angle cameras located at the South African Astronomical Observatory.^[7]^[8]^[1] Analysis of over 4000 images taken between May and November 2006 resulted in the detection of a transit occurring every 1.3 days. Follow-up radial velocity observations using the Swiss 1.2-metre Leonhard Euler Telescope confirmed that the transiting object was a planet.^[1]

Characteristics

The planetary equilibrium temperature would be 1650±30 K,^[9] but the measured dayside temperature is higher, with a 2015 study finding 1900±100 K^[10] and a 2020 study finding 1957±68 K.^[4]

A study in 2012, utilizing the Rossiter–McLaughlin effect, determined the planetary orbit is probably aligned with the equatorial plane of the star, with misalignment equal to -1⁺¹⁴
₋₁₂°.^[11]

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. The anomalously high rate of orbital decay of WASP-4b is poorly understood as of 2021.^[2]

References

^ ^a ^b ^c 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.
^ ^a ^b ^c 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 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. S2CID 118923163.
^ ^a ^b Wong, Ian; Shporer, Avi; Daylan, Tansu; Benneke, Björn; Fetherolf, Tara; Kane, Stephen R.; Ricker, George R.; Vanderspek, Roland; Latham, David W.; Winn, Joshua N.; Jenkins, Jon M.; Boyd, Patricia T.; Glidden, Ana; Goeke, Robert F.; Sha, Lizhou; Ting, Eric B.; Yahalomi, Daniel (2020), "Systematic Phase Curve Study of Known Transiting Systems from Year One of the TESS Mission", The Astronomical Journal, 160 (4): 155, arXiv:2003.06407, Bibcode:2020AJ....160..155W, doi:10.3847/1538-3881/ababad, S2CID 212717799
^ Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
^ Roman, Nancy G. (1987). "Identification of a Constellation From a Position". Publications of the Astronomical Society of the Pacific. 99 (617): 695–699. Bibcode:1987PASP...99..695R. doi:10.1086/132034. Vizier query form
^ Sherriff, Lucy (2007-10-31). "UK boffins ID three new exo-planets". The Register. Retrieved 2018-09-23.
^ "Astronomer discovers new planets". BBC News. 2007-10-31. Retrieved 2018-09-23.
^ Table 3, Improved parameters for the transiting hot Jupiters WASP-4b and WASP-5b, M. Gillon et al., Astronomy and Astrophysics 496, #1 (2009), pp. 259–267, doi:10.1051/0004-6361:200810929, Bibcode:2009A&A...496..259G.
^ Zhou, G.; Bayliss, D. D. R.; Kedziora-Chudczer, L.; Tinney, C. G.; Bailey, J.; Salter, G.; Rodriguez, J. (2015). "Secondary eclipse observations for seven hot-Jupiters from the Anglo-Australian Telescope". Monthly Notices of the Royal Astronomical Society. 454 (3): 3002–3019. arXiv:1509.04147. Bibcode:2015MNRAS.454.3002Z. doi:10.1093/mnras/stv2138.
^ Albrecht, Simon; Winn, Joshua N.; Johnson, John A.; Howard, Andrew W.; Marcy, Geoffrey W.; Butler, R. Paul; Arriagada, Pamela; Crane, Jeffrey D.; Shectman, Stephen A.; Thompson, Ian B.; Hirano, Teruyuki; Bakos, Gaspar; Hartman, Joel D. (2012), "Obliquities of Hot Jupiter Host Stars: Evidence for Tidal Interactions and Primordial Misalignments", The Astrophysical Journal, 757 (1): 18, arXiv:1206.6105, Bibcode:2012ApJ...757...18A, doi:10.1088/0004-637X/757/1/18, S2CID 17174530

External links

Media related to WASP-4b at Wikimedia Commons

"Transiting exoplanets from the Wide Angle Search for Planets". WASP Planets. Coel Hellier. Retrieved 2020-12-27.
"UK planet hunters announce three new finds" (PDF). 2007-10-30. Archived from the original (PDF) on 2008-05-16. Retrieved 2008-07-02.

Constellation of Phoenix

Stars

Bayer	α (Ankaa) β γ δ ε ζ (Wurren) η θ ι κ λ¹ λ² μ ν ξ π ρ σ τ υ φ χ ψ ω
Variable	RV SX YZ AD AE AI AW AZ BB BD
HR	6 23 73 109 111 120 140 148 162 171 198 202 209 229 299 350 408 411 443 447 519 524 537 574 588 632 636 659 686 698 706 8910 8920 8929 8959 8993 9001 9046 9077 9082
HD	2039 5388 6434 (Nenque) 8535 9895 11421 13218 13387 223549 224782
Other	CD-44 170 BPM 30551 HE 0107-5240 NGC 405 WASP-4 WASP-5 WASP-18 WASP-29 WASP-96 WD 2359-434