HAT-P-27, also known as WASP-40, is the primary of a binary star system about 659 light-years away. It is a G-type main-sequence star. The star's age is similar to the Sun's at 4.4 billion years.[2] HAT-P-27 is enriched in heavy elements, having a 195% concentration of iron compared to the Sun.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Virgo |
| Right ascension | 14h 51m 04.1870s[1] |
| Declination | +05° 56′ 50.549″[1] |
| Apparent magnitude (V) | 12.214[2] |
| Characteristics | |
| Evolutionary stage | main-sequence star |
| Spectral type | G8 |
| Astrometry | |
| Radial velocity (Rv) | -15.901[3] km/s |
| Proper motion (μ) | RA: −28.610(19) mas/yr[1] Dec.: −2.774(19) mas/yr[1] |
| Parallax (π) | 4.952 ± 0.0169 mas[1] |
| Distance | 659 ± 2 ly (201.9 ± 0.7 pc) |
| Orbit[4] | |
| Primary | HAT-P-27 |
| Companion | HAT-P-27 B |
| Semi-major axis (a) | 0.656±0.021" (131 AU) |
| Details[2] | |
| Mass | 0.945±0.035 M☉ |
| Radius | 0.898+0.054 −0.039 R☉ |
| Luminosity | 0.57+0.09 −0.07 L☉ |
| Surface gravity (log g) | 4.51±0.04 cgs |
| Temperature | 5300±90 K |
| Metallicity [Fe/H] | 0.29±0.10 dex |
| Rotation | 0.4±0.4 |
| Rotational velocity (v sin i) | 0.6+0.7 −0.4[5] km/s |
| Age | 4.4+3.8 −2.6 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The very dim stellar companion was detected in 2015 at a projected separation of 0.656″[4] and proven to be physically bound to the system in 2016.[6]
Planetary system
editIn 2011 a transiting hot Jupiter type planet b was detected in a mildly eccentric orbit. The planetary equilibrium temperature is 1207±41 K.[2] The survey in 2013 failed to find any Rossiter-McLaughlin effect and therefore was unable to constrain the inclination of planetary orbit to the equatorial plane of the parent star.[5] No orbital decay was detected as in 2018, despite the close proximity of the planet to the star.[7]
The presence of an additional planet in the system has been suspected since 2015.[8]
In 2024, a detection of a possible neptunian exoplanet was reported. It is expected to be analog with Neptune in terms of radius, although is much hotter due to the low orbital separation, one year in this planet last one day and five hours, causing the planetary equilibrium temperature to be 1,426 K (1,153 °C). More observations are needed to validate its existence.[9]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 0.660±0.033 MJ | 0.0403±0.0005 | 3.039586±0.000012 | 0.078±0.047 | 85.0±0.2[5]° | 1.038+0.077 −0.058 RJ |
| c (unconfirmed) | 17.8+13.8 −0.81 M🜨 |
— | 1.1994(2) | <0.19 | — | 4.33±0.44 R🜨 |
References
edit- ^ a b c d 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 Béky, B.; Bakos, G. Á.; Hartman, J.; Torres, G.; Latham, D. W.; Jordán, A.; Arriagada, P.; Bayliss, D.; Kiss, L. L.; Kovács, Géza; Quinn, S. N.; Marcy, G. W.; Howard, A. W.; Fischer, D. A.; Johnson, J. A.; Esquerdo, G. A.; Noyes, R. W.; Buchhave, L. A.; Sasselov, D. D.; Stefanik, R. P.; Perumpilly, G.; Lázár, J.; Papp, I.; Sári, P. (2011), "HAT-P-27b: A HOT JUPITER TRANSITING A G STAR ON A 3 DAY ORBIT", The Astrophysical Journal, 734 (2): 109, arXiv:1101.3511, Bibcode:2011ApJ...734..109B, doi:10.1088/0004-637X/734/2/109, S2CID 31357299
- ^ a b "HAT-P-27". SIMBAD. Centre de données astronomiques de Strasbourg.
- ^ a b Wöllert, Maria; Brandner, Wolfgang (2015), "A Lucky Imaging search for stellar sources near 74 transit hosts", Astronomy & Astrophysics, 579: A129, arXiv:1506.05456, Bibcode:2015A&A...579A.129W, doi:10.1051/0004-6361/201526525, S2CID 118903879
- ^ a b c Brown, D. J. A.; Collier Cameron, A.; Díaz, R. F.; Doyle, A. P.; Gillon, M.; Lendl, M.; Smalley, B.; Triaud, A. H. M. J.; Anderson, D. R.; Enoch, B.; Hellier, C.; Maxted, P. F. L.; Miller, G. R. M.; Pollacco, D.; Queloz, D.; Boisse, I.; Hébrard, G. (2013), "Analysis of Spin-Orbit Alignment in the Wasp-32, Wasp-38, and Hat-P-27/Wasp-40 Systems", The Astrophysical Journal, 760 (2): 139, arXiv:1303.5649, Bibcode:2012ApJ...760..139B, doi:10.1088/0004-637X/760/2/139, S2CID 54033638
- ^ Ngo, Henry; Knutson, Heather A.; Hinkley, Sasha; Bryan, Marta; Crepp, Justin R.; Batygin, Konstantin; Crossfield, Ian; Hansen, Brad; Howard, Andrew W.; Johnson, John A.; Mawet, Dimitri; Morton, Timothy D.; Muirhead, Philip S.; Wang, Ji (2016), "FRIENDS OF HOT JUPITERS. IV. STELLAR COMPANIONS BEYOND 50 au MIGHT FACILITATE GIANT PLANET FORMATION, BUT MOST ARE UNLIKELY TO CAUSE KOZAI–LIDOV MIGRATION", The Astrophysical Journal, 827 (1): 8, arXiv:1606.07102, Bibcode:2016ApJ...827....8N, doi:10.3847/0004-637X/827/1/8, S2CID 41083068
- ^ Penev, Kaloyan; Bouma, L. G.; Winn, Joshua N.; Hartman, Joel D. (2018), "EMPIRICAL TIDAL DISSIPATION IN EXOPLANET HOSTS FROM TIDAL SPIN–UP", The Astronomical Journal, 155 (4): 165, arXiv:1802.05269, Bibcode:2018AJ....155..165P, doi:10.3847/1538-3881/aaaf71, PMC 6510550, PMID 31080254, S2CID 64370118
- ^ Ground-based transit observations of the HAT-P-18, HAT-P-19, HAT-P-27/WASP40 and WASP-21 systems
- ^ a b Dévora-Pajares, Martín; Pozuelos, Francisco J.; Thuillier, Antoine; Timmermans, Mathilde; Van Grootel, Valérie; Bonidie, Victoria; Mota, Luis Cerdeño; Suárez, Juan C. (2024). "The SHERLOCK pipeline: new exoplanet candidates in the WASP-16, HAT-P-27, HAT-P-26, and TOI-2411 systems". Monthly Notices of the Royal Astronomical Society. arXiv:2407.14602. doi:10.1093/mnras/stae1740.
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