WASP-39
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Virgo[2] |
| Right ascension | 14h 29m 18.41517s[3] |
| Declination | −03° 26′ 40.2045″[3] |
| Apparent magnitude (V) | 12.11[4] |
| Characteristics | |
| Evolutionary stage | main sequence[4] |
| Spectral type | G8[4] |
| Variable type | planetary transit[5] |
| Astrometry | |
| Radial velocity (Rv) | −58.51±0.83[3] km/s |
| Proper motion (μ) | RA: -19.041 mas/yr[3] Dec.: +0.437 mas/yr[3] |
| Parallax (π) | 4.6435±0.0144 mas[3] |
| Distance | 702 ± 2 ly (215.4 ± 0.7 pc) |
| Details[4] | |
| Mass | 0.93±0.03 M☉ |
| Radius | 0.895±0.023 R☉ |
| Luminosity | 0.63[6] L☉ |
| Surface gravity (log g) | 4.4±0.2 cgs |
| Temperature | 5400±150 K |
| Metallicity [Fe/H] | −0.12±0.10 dex |
| Rotational velocity (v sin i) | 1.4±0.6 km/s |
| Age | 9+3 −4 Gyr |
| Other designations | |
| Malmok, V732 Vir, TOI-5675, TIC 181949561, WASP-39, 2MASS J14291840-0326403[7] | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
WASP-39, also named Malmok, is a G-type main-sequence star about 702 light-years (215 parsecs) away in the constellation Virgo. With an apparent magnitude of 12.1, it is much too faint to be visible to the naked eye. The star is slightly smaller and cooler than the Sun. It hosts one known exoplanet, WASP-39b.
Nomenclature
[edit]The designation WASP-39 comes from the Wide Angle Search for Planets. Since the planet transits the star, the star is classified as a planetary transit variable and has received the variable star designation V732 Virginis.[5]
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 Aruba.[8] The approved names were Malmok for the star and Bocaprins for the planet, named after Malmok and Boca Prins, both beaches in Aruba.[9][10]
Planetary system
[edit]The planet WASP-39b, later named Bocaprins, is a low-density hot Jupiter, about the mass of Saturn but larger, discovered in 2011 by the Wide Angle Search for Planets using the transit method.[4] Its orbit is aligned with the star's equator.[11] It has been a target for observation by the Hubble Space Telescope[12] and James Webb Space Telescope,[13] which have identified water vapor,[14] carbon dioxide,[15] and sulfur dioxide in its atmosphere.[16]
There is evidence of a possible circumstellar disk around WASP-39, farther than 2 au from the star.[17]
| Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b / Bocaprins | 0.275+0.042 −0.043 MJ | 0.04859+0.00051 −0.00053 | 4.05529470(97) | <0.048 | 87.83+0.25 −0.22° | 1.27±0.04 RJ |
References
[edit]- ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 24 June 2025.
- ^ 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.
- ^ a b c d e 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.
- ^ a b c d e Faedi, F.; Barros, S. C. C.; et al. (July 2011). "WASP-39b: a highly inflated Saturn-mass planet orbiting a late G-type star". Astronomy & Astrophysics. 531: A40. arXiv:1102.1375. Bibcode:2011A&A...531A..40F. doi:10.1051/0004-6361/201116671.
- ^ a b "V732 Vir". General Catalog of Variable Stars - VizieR. Retrieved 24 June 2025.
- ^ Yu, Jie; Khanna, Shourya; Themessl, Nathalie; Hekker, Saskia; Dréau, Guillaume; Gizon, Laurent; Bi, Shaolan (2023). "Revised Extinctions and Radii for 1.5 Million Stars Observed by APOGEE, GALAH, and RAVE". The Astrophysical Journal Supplement Series. 264 (2): 41. arXiv:2206.00046. Bibcode:2023ApJS..264...41Y. doi:10.3847/1538-4365/acabc8.
- ^ "WASP-39". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 24 June 2025.
- ^ "Naming". WASP Planets. 24 June 2019. Retrieved 24 June 2025.
- ^ "Approved names". NameExoWorlds. IAU. Retrieved 24 June 2025.
- ^ "Aruba". NameExoWorlds. IAU. Retrieved 24 June 2025.
- ^ Mancini, L.; Esposito, M.; et al. (May 2018). "The GAPS programme with HARPS-N at TNG. XVI. Measurement of the Rossiter-McLaughlin effect of transiting planetary systems HAT-P-3, HAT-P-12, HAT-P-22, WASP-39, and WASP-60". Astronomy & Astrophysics. 613: A41. arXiv:1802.03859. Bibcode:2018A&A...613A..41M. doi:10.1051/0004-6361/201732234.
- ^ Fischer, Patrick D.; Knutson, Heather A.; et al. (August 2016). "HST Hot-Jupiter Transmission Spectral Survey: Clear Skies for Cool Saturn WASP-39b". The Astrophysical Journal. 827 (1): 19. arXiv:1601.04761. Bibcode:2016ApJ...827...19F. doi:10.3847/0004-637X/827/1/19.
- ^ Carter, A. L.; May, E. M.; et al. (August 2024). "A benchmark JWST near-infrared spectrum for the exoplanet WASP-39 b". Nature Astronomy. 8 (8): 1008–1019. arXiv:2407.13893. Bibcode:2024NatAs...8.1008C. doi:10.1038/s41550-024-02292-x.
- ^ Wakeford, H. R.; Sing, D. K.; et al. (January 2018). "The Complete Transmission Spectrum of WASP-39b with a Precise Water Constraint". The Astronomical Journal. 155 (1): 29. arXiv:1711.10529. Bibcode:2018AJ....155...29W. doi:10.3847/1538-3881/aa9e4e.
- ^ Ahrer, Eva-Maria; et al. (JWST Transiting Exoplanet Community Early Release Science Team) (February 2023). "Identification of carbon dioxide in an exoplanet atmosphere". Nature. 614 (7949): 649–652. arXiv:2208.11692. Bibcode:2023Natur.614..649J. doi:10.1038/s41586-022-05269-w. PMC 9946830. PMID 36055338.
- ^ Tsai, Shang-Min; Lee, Elspeth K. H.; et al. (May 2023). "Photochemically produced SO2 in the atmosphere of WASP-39b". Nature. 617 (7961): 483–487. arXiv:2211.10490. Bibcode:2023Natur.617..483T. doi:10.1038/s41586-023-05902-2. PMID 37100917.
- ^ Flagg, Laura; Weinberger, Alycia J.; et al. (July 2024). "Debris Disks Can Contaminate Mid-infrared Exoplanet Spectra: Evidence for a Circumstellar Debris Disk around Exoplanet Host WASP-39". The Astrophysical Journal Letters. 969 (1): L1. arXiv:2406.02305. Bibcode:2024ApJ...969L..19F. doi:10.3847/2041-8213/ad4649.
- ^ 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.
