| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Sextans[1] |
| Right ascension | 10h 42m 14.0837s[2] |
| Declination | −03° 50′ 06.260″[2] |
| Apparent magnitude (V) | 10.165(46)[3] |
| Characteristics | |
| Spectral type | G5[4] |
| Apparent magnitude (J) | 9.092(29)[5] |
| Apparent magnitude (H) | 8.738(55)[5] |
| Apparent magnitude (K) | 8.641(19)[5] |
| Variable type | Planetary transit[4] |
| Astrometry | |
| Radial velocity (Rv) | −8.92(6)[6] km/s |
| Proper motion (μ) | RA: 19.133(20) mas/yr[2] Dec.: 17.058(18) mas/yr[2] |
| Parallax (π) | 6.2241 ± 0.0175 mas[2] |
| Distance | 524 ± 1 ly (160.7 ± 0.5 pc) |
| Details[7] | |
| Mass | 0.949+0.022 −0.019[8] M☉ |
| Radius | 1.335+0.025 −0.029[8] R☉ |
| Surface gravity (log g) | 4.23(2) cgs |
| Temperature | 5842(14) K |
| Metallicity [Fe/H] | −0.19(1) dex |
| Rotational velocity (v sin i) | 0.53+0.07 −0.05 km/s |
| Age | 9.656(1.002) Gyr |
| Other designations | |
WASP-127 is an old G5 type star. There is so far one planet detected, a low density sub-Saturn type.[4]
Stellar system edit
WASP-127 is a G5-type star, less massive but with a radius about 30% larger than the Sun's. It is nearing the end of its main sequence phase at 9.7 billion years old and is transitioning into its subgiant phase. The star is photometrically stable, and slowly rotating.[7]
Planetary system edit
Currently, one planet is known to orbit WASP-127, which is described as either a super-Neptune or a sub-Saturn planet with a mass 16% that of Jupiter and a heavily inflated radius 1.3 times that of Jupiter. This results in it being one of the least dense planets known. It orbits its star in just over 4 days.[8][6]
WASP-127b edit
Discovery edit
WASP-127b, along with WASP-136b and WASP-138b, was discovered by the Wide Angle Search for Planets. The host star, WASP-127, was monitored from 2006 to 2014, accumulating 87,349 photometric data points. Analysis of this data resulted in the discovery of the transits of WASP-127b across the face of its parent star. Follow-up photometry from various telescopes was utilized to refine the system parameters. Radial velocity measurements, conducted by the CORALIE spectrograph and the SOPHIE échelle spectrograph, served to confirm the planet's presence and ascertain its mass.[4]
Characteristics edit
A study of the secondary Eclipse, when the planet passes behind its host star, by the Spitzer Space Telescope found that the best-fit eclipse phases for WASP-127b are consistent with the expectation for a circular orbit.[10]
Observations using the ESPRESSO spectrograph at the European Southern Observatory's Very Large Telescope indicate that WASP-127b, unlike the planets in our Solar System, orbits in the opposite direction to its star and on a different plane than the equatorial one. This is an unusual alignment for a hot Saturn within an ancient stellar system and may suggest the presence of an unseen companion.[7][11][12]
Atmosphere edit
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 0.1647+0.0214 −0.0172 MJ |
0.04840+0.00136 −0.00095 |
4.17806473(25)[13] | 0.0 (fixed)[10] | 87.84+0.36 −0.33° |
1.311+0.025 −0.029 RJ |
References edit
- ^ 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
- ^ 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.
- ^ 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
- ^ a b c d Lam, K. W. F.; et al. (2017). "From dense hot Jupiter to low-density Neptune: The discovery of WASP-127b, WASP-136b, and WASP-138b". Astronomy & Astrophysics. 599 A3. arXiv:1607.07859. Bibcode:2017A&A...599A...3L. doi:10.1051/0004-6361/201629403.
- ^ a b c Skrutskie, M. F.; et al. (2006). "The Two Micron All Sky Survey (2MASS)". The Astronomical Journal. 131 (2): 1163–1183. Bibcode:2006AJ....131.1163S. doi:10.1086/498708. Vizier catalog entry
- ^ a b Boucher, Anne; et al. (2023-04-26). "CO or no CO? Narrowing the CO abundance constraint and recovering the H2O detection in the atmosphere of WASP-127 b using SPIRou". Monthly Notices of the Royal Astronomical Society. 522 (4). Oxford University Press (OUP): 5062–5083. arXiv:2303.03232. Bibcode:2023MNRAS.522.5062B. doi:10.1093/mnras/stad1247.
- ^ a b c Allart, R.; et al. (2020). "WASP-127b: a misaligned planet with a partly cloudy atmosphere and tenuous sodium signature seen by ESPRESSO". Astronomy & Astrophysics. 644 A155. arXiv:2010.15143. Bibcode:2020A&A...644A.155A. doi:10.1051/0004-6361/202039234.
- ^ a b c d Seidel, J. V.; et al. (2020). "Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS): VI. Non-detection of sodium with HARPS on the bloated super-Neptune WASP-127b". Astronomy & Astrophysics. 643 A45. arXiv:2009.13386. Bibcode:2020A&A...643A..45S. doi:10.1051/0004-6361/202039058.
- ^ "Wasp-127". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2024-04-19.
- ^ a b Wallack, Nicole L.; et al. (2021-07-01). "Trends in Spitzer Secondary Eclipses". The Astronomical Journal. 162 (1) 36. arXiv:2103.15833. Bibcode:2021AJ....162...36W. doi:10.3847/1538-3881/abdbb2.
- ^ Cristo, E.; et al. (2022). "CaRM: Exploring the chromatic Rossiter-McLaughlin effect: The cases of HD 189733b and WASP-127b". Astronomy & Astrophysics. 660 A52. arXiv:2201.06531. Bibcode:2022A&A...660A..52C. doi:10.1051/0004-6361/202142353.
- ^ "Cloud-spotting on a distant exoplanet" (Press release). Europlanet Society. 2021-09-23. Retrieved 2024-05-25.
- ^ Wang, Wenqin; et al. (2024-01-01). "Long-term Variations in the Orbital Period of Hot Jupiters from Transit-timing Analysis Using TESS Survey Data". The Astrophysical Journal Supplement Series. 270 (1) 14. Table 2. arXiv:2310.17225. Bibcode:2024ApJS..270...14W. doi:10.3847/1538-4365/ad0847.
