Astronomy:Kepler-33
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Cygnus |
| Right ascension | 19h 16m 18.6100s[1] |
| Declination | +46° 00′ 18.814″[1] |
| Apparent magnitude (V) | 13.988 |
| Characteristics | |
| Spectral type | G1IV |
| Astrometry | |
| Radial velocity (Rv) | 12.18±3.65[1] km/s |
| Proper motion (μ) | RA: −1.107(15)[1] mas/yr Dec.: −13.099(14)[1] mas/yr |
| Parallax (π) | 0.8136 ± 0.0118[1] mas |
| Distance | 4,010 ± 60 ly (1,230 ± 20 pc) |
| Details[2] | |
| Mass | 1.26+0.03 −0.06 M☉ |
| Radius | 1.66±0.03 R☉ |
| Luminosity | 3.1+0.2 −0.1 L☉ |
| Temperature | 5947±60 K |
| Metallicity [Fe/H] | 0.14±0.04 dex |
| Age | 4.2+1.3 −0.3 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Kepler-33 is a star about 4,000 light-years (1,200 parsecs) in the constellation of Cygnus, with a system of five known planets. Having just begun to evolve off from the main sequence,[4] its radius and mass are difficult to ascertain, although data available in 2020 shows its best-fit mass of 1.3M☉ and radius of 1.6R☉ are compatible with a model of a subgiant star.[5]
Planetary system
The first detections of the candidate four-body planetary system were reported in February 2011.[6] On January 26, 2012, the planetary system around the star was confirmed, including a fifth planet.[4] However, unlike some other planets confirmed via Kepler, their masses were initially not known, as Doppler spectroscopy measurements were not done before the announcement. Judging by their radii, b may be a large super-Earth or small hot Neptune while the other four are all likely to be the latter. (As of 2022), the masses of planets e & f have been measured, with upper limits on the masses of planets c & d. These mass measurements confirm Kepler-33 d, e & f to be low-density, gaseous planets.[2]
Planets b and c may actually be in a 7:3 resonance, as there is a 0.05 day discrepancy; there is also a small 0.18 day discrepancy between a 5:3 resonance between planets c and d. The other planets do not seem to be in any resonances, though near resonances are 3d:2e and 4e:3f.
The planetary system in its current configuration is highly susceptible to perturbations, therefore assuming stability, no additional giant planets can be located within 30 AU from the parent star.[7]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | — | 0.0673+0.0004 −0.0012 |
5.66816±0.00005 | <0.2 | >87.0° | 1.54+0.06 −0.05 R⊕ |
| c | <19 M⊕ | 0.1181+0.0008 −0.0020 |
13.17552±0.00005 | <0.05 | >88.6° | 2.73±0.06 R⊕ |
| d | <8.2 M⊕ | 0.165+0.001 −0.003 |
21.77574+0.00006 −0.00004 |
<0.03 | >89.02° | 4.67±0.09 R⊕ |
| e | 6.6+1.1 −1.0 M⊕ |
0.212+0.001 −0.004 |
31.7852±0.0002 | <0.02 | 89.4±0.1° | 3.54+0.09 −0.07 R⊕ |
| f | 8.2+1.6 −1.2 M⊕ |
0.252+0.002 −0.004 |
41.0274±0.0002 | <0.02 | 89.7+0.2 −0.1° |
3.96+0.09 −0.07 R⊕ |
See also
References
- ↑ 1.0 1.1 1.2 1.3 1.4 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 Sikora, James et al. (December 2022). "Refining the Masses and Radii of the Star Kepler-33 and its Five Transiting Planets". The Astronomical Journal 164 (6): 242. doi:10.3847/1538-3881/ac98c4. Bibcode: 2022AJ....164..242S.
- ↑ "Notes for star Kepler-33". Extrasolar Planets Encyclopaedia. http://exoplanet.eu/star.php?st=Kepler-33.
- ↑ 4.0 4.1 Lissauer, Jack J.; Marcy, Geoffrey W.; Rowe, Jason F.; Bryson, Stephen T.; Adams, Elisabeth; Buchhave, Lars A.; Ciardi, David R.; Cochran, William D. et al. (10 May 2012). "Almost All of Kepler's Multiple Planet Candidates are Planets". The Astrophysical Journal 750 (2): 112. doi:10.1088/0004-637X/750/2/112. Bibcode: 2012ApJ...750..112L.
- ↑ Berger, Travis A.; Huber, Daniel; van Saders, Jennifer L.; Gaidos, Eric; Tayar, Jamie; Kraus, Adam L. (2020), "The Gaia-Kepler Stellar Properties Catalog. I. Homogeneous Fundamental Properties for 186,301 Kepler Stars", The Astronomical Journal 159 (6): 280, doi:10.3847/1538-3881/159/6/280, Bibcode: 2020AJ....159..280B
- ↑ Ford, Eric B.; Rowe, Jason F.; Fabrycky, Daniel C.; Carter, Joshua A.; Holman, Matthew J.; Lissauer, Jack J.; Ragozzine, Darin; Steffen, Jason H. et al. (2011), "Transit Timing Observations from Kepler : I. Statistical Analysis of the First Four Months", The Astrophysical Journal Supplement Series 197 (1): 2, doi:10.1088/0067-0049/197/1/2, Bibcode: 2011ApJS..197....2F
- ↑ Becker, Juliette C.; Adams, Fred C. (2017), "Effects of Unseen Additional Planetary Perturbers on Compact Extrasolar Planetary Systems", Monthly Notices of the Royal Astronomical Society 468 (1): 549–563, doi:10.1093/mnras/stx461, Bibcode: 2017MNRAS.468..549B
Coordinates: 
19h 16m 18.61s, +46° 00′ 18.8″
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