Article · Wikipedia archive · Last revised Jul 23, 2026

WASP-19

WASP-19, formally named Wattle, is a magnitude 12.3 star about 869 light-years away, located in the Vela constellation of the Southern Hemisphere. This star has been found to host a transiting hot Jupiter-type planet in a tight orbit.

Last revised
Jul 23, 2026
Read time
≈ 3 min
Length
775 w
Citations
29
Source
WASP-19 / Wattle
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Vela1
Right ascension 09h 53m 40.07656s2
Declination −45° 39′ 33.0572″2
Apparent magnitude (V) 12.312 ± 0.0173
Characteristics
Evolutionary stage main sequence2
Spectral type G8V4
Apparent magnitude (B) 13.055
Apparent magnitude (R) 12.125
Apparent magnitude (I) 11.355
Apparent magnitude (J) 10.911 ± 0.0266
Apparent magnitude (H) 10.602 ± 0.0226
Apparent magnitude (K) 10.481 ± 0.0236
B−V color index 1.3
V−R color index 0.1
R−I color index 0.82
Variable type planetary transit
Astrometry
Radial velocity (Rv)21.41±0.952 km/s
Proper motion (μ) RA: −35.457 mas/yr2
Dec.: 17.378 mas/yr2
Parallax (π)3.7516±0.0090 mas2
Distance869 ± 2 ly
(266.6 ± 0.6 pc)
Absolute magnitude (MV)5.3
Details7
Mass0.965+0.091
−0.095
 M
Radius1.006+0.031
−0.034
 R
Luminosity0.905+0.071
−0.069
 L
Surface gravity (log g)4.417+0.020
−0.021
 cgs
Temperature5616+66
−65
 K
Metallicity [Fe/H]0.04+0.25
−0.30
 dex
Rotation11.76±0.09 d8
Rotational velocity (v sin i)4.0 ± 1.09 km/s
Age6.4+4.1
−3.5
 Gyr
Other designations
Wattle, TOI-655, TIC 35516889, WASP-19, GSC 08181-01711, 2MASS J09534008-4539330, USNO-B1.0 0443-001931115
Database references
SIMBADdata
Exoplanet Archivedata

WASP-19, formally named Wattle,10 is a magnitude 12.3 star about 869 light-years (266 parsecs) away, located in the Vela constellation of the Southern Hemisphere.4 This star has been found to host a transiting hot Jupiter-type planet in a tight orbit.

WASP-19 is older than the Sun, has a fraction of heavy elements above the solar abundance, and is rotating rapidly, being spun up by the tides raised by the giant planet on a close orbit.8

Nomenclature

The designation WASP-19 indicates that this was the 19th star found to have a planet by the Wide Angle Search for Planets.

In August 2022, this planetary system was included among 20 systems to be named by the third NameExoWorlds project.11 The approved names were proposed by a team from Brandon Park Primary School in Wheelers Hill (Melbourne, Australia), led by scientist Lance C. Kelly and teacher David Maierhofer1213 and announced in June 2023. WASP-19 is named "Wattle" and its planet is named "Banksia", after the plant genera Wattle (specifically the golden wattle Acacia pycnantha) and Banksia (specifically the scarlet banksia Banksia coccinea) respectively.10

Planetary system

In December 2009, the SuperWASP project announced that a hot Jupiter type exoplanet, WASP-19b, was orbiting very close to this star and with the shortest orbital period of any transiting exoplanet known at the time.4

The WASP-19 planetary system7
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination
(°)
Radius
b / Banksia 1.154+0.078
−0.080
 MJ
0.01652+0.00050
−0.00056
0.78883852(82) 0.0126+0.014
−0.0089
79.08+0.34
−0.37
1.415+0.044
−0.048
 RJ
References

References

  1. Roman, Nancy G. (1987). "Identification of a constellation from a position". Publications of the Astronomical Society of the Pacific. 99 (617): 695. Bibcode:1987PASP...99..695R. doi:10.1086/132034. Constellation record for this object at VizieR.
  2. 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.
  3. Maxted, P. F. L.; et al. (2011). "UBV(RI)C photometry of transiting planet hosting stars". Monthly Notices of the Royal Astronomical Society. 418 (2): 1039–1042. arXiv:1108.0349. Bibcode:2011MNRAS.418.1039M. doi:10.1111/j.1365-2966.2011.19554.x. S2CID 117056033.
  4. Hebb, L.; et al. (2010). "WASP-19b: The Shortest Period Transiting Exoplanet Yet Discovered". The Astrophysical Journal. 708 (1): 224–231. arXiv:1001.0403. Bibcode:2010ApJ...708..224H. doi:10.1088/0004-637X/708/1/224. S2CID 119189785.
  5. "WASP-19". SIMBAD. Centre de données astronomiques de Strasbourg.
  6. Skrutskie, Michael F.; Cutri, Roc M.; Stiening, Rae; Weinberg, Martin D.; Schneider, Stephen E.; Carpenter, John M.; Beichman, Charles A.; Capps, Richard W.; Chester, Thomas; Elias, Jonathan H.; Huchra, John P.; Liebert, James W.; Lonsdale, Carol J.; Monet, David G.; Price, Stephan; Seitzer, Patrick; Jarrett, Thomas H.; Kirkpatrick, J. Davy; Gizis, John E.; Howard, Elizabeth V.; Evans, Tracey E.; Fowler, John W.; Fullmer, Linda; Hurt, Robert L.; Light, Robert M.; Kopan, Eugene L.; Marsh, Kenneth A.; McCallon, Howard L.; Tam, Robert; Van Dyk, Schuyler D.; Wheelock, Sherry L. (1 February 2006). "The Two Micron All Sky Survey (2MASS)". The Astronomical Journal. 131 (2): 1163–1183. Bibcode:2006AJ....131.1163S. doi:10.1086/498708. ISSN 0004-6256. S2CID 18913331. Vizier catalog entry
  7. Cortés-Zuleta, Pía; Rojo, Patricio; et al. (April 2020). "TraMoS. V. Updated ephemeris and multi-epoch monitoring of the hot Jupiters WASP-18Ab, WASP-19b, and WASP-77Ab". Astronomy & Astrophysics. 636: A98. arXiv:2001.11112. Bibcode:2020A&A...636A..98C. doi:10.1051/0004-6361/201936279. S2CID 241596186.
  8. 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
  9. Torres, Guillermo; et al. (2012). "Improved Spectroscopic Parameters for Transiting Planet Hosts". The Astrophysical Journal. 757 (2). 161. arXiv:1208.1268. Bibcode:2012ApJ...757..161T. doi:10.1088/0004-637X/757/2/161. S2CID 16580774.
  10. "2022 Approved Names". nameexoworlds.iau.org. IAU. Retrieved 7 June 2023.
  11. "List of ExoWorlds 2022". nameexoworlds.iau.org. IAU. 8 August 2022. Retrieved 27 August 2022.
  12. "Facebook". www.facebook.com.
  13. https://nameexoworlds.iau.org/2022approved-names?pgid=lieirelz-ee6d54d6-a64c-4708-a2d5-d7ceb7071768,
Further reading

Further reading