KELT-1 is a F-type main-sequence star. Its surface temperature is 6518±50 K. It is similar to the Sun in its concentration of heavy elements, with a metallicity Fe/H index of 0.008±0.073, but is much younger at an age of 1.75±0.25 billion years. The star is rotating very rapidly.[2]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Andromeda |
| Right ascension | 00h 01m 26.9169s[1] |
| Declination | 39° 23′ 01.7821″[1] |
| Apparent magnitude (V) | 10.63 |
| Characteristics | |
| Evolutionary stage | main-sequence star |
| Spectral type | F[2] |
| Astrometry | |
| Radial velocity (Rv) | 1.296[3] km/s |
| Proper motion (μ) | RA: -9.696[3] mas/yr Dec.: -7.823[3] mas/yr |
| Parallax (π) | 3.6836 ± 0.0144 mas[3] |
| Distance | 885 ± 3 ly (271 ± 1 pc) |
| Position (relative to KELT-1)[2] | |
| Component | KELT-1B |
| Epoch of observation | 2012 |
| Angular distance | 0.588±0.001″ |
| Position angle | 157.4±0.2° |
| Projected separation | 154±8 AU |
| Details[2] | |
| Mass | 1.324±0.026 M☉ |
| Radius | 1.462+0.037 −0.024 R☉ |
| Luminosity | 3.11±0.05[4] L☉ |
| Surface gravity (log g) | 4.229+0.012 −0.019 cgs |
| Temperature | 6518±50 K |
| Metallicity [Fe/H] | 0.008±0.073 dex |
| Rotational velocity (v sin i) | 55 km/s |
| Age | 1.75±0.25 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
A red dwarf stellar companion at a projected separation of 154±8 AU was detected in 2012, simultaneously with a planetary companion.[2]
Planetary system
editThe star was found to be orbited by a low-mass brown dwarf or giant planet in 2012.[2]
The atmosphere of the brown dwarf KELT-1b has been extensively measured from space- and ground-based observatories by a team of astronomers led by Thomas Beatty. They found that KELT-1b has an equilibrium temperature of 2422+32
−26 K,[2] but features a very strong contrast between measured dayside and nightside temperatures. Dayside temperature appears to be 3340±110 K,[5] while nightside temperature is 1173+175
−130 K.[6] The excess dayside temperature may be an artifact arising from highly reflective (dayside albedo reaching 0.5, which is unusual for hot planets and brown dwarfs) rock-vapor clouds. Also, the brightest band is shifted eastward from the subsolar point by 18.3±7.4°.[5]
KELT-1b's density of 22.1+5.62
−9.16 g/cm3 is the highest among well characterized planets.[4]
The planetary orbit is well aligned with the equatorial plane of the star, with the misalignment angle equal to 2±16°.[2] Despite the short orbital period, orbital decay of KELT-1b has not been detected as of 2018.[7]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 27.23+0.50 −0.48 MJ |
0.02466±0.00016 | 1.21749397 | 0 | 85.3+2.9 −2.6° |
1.15+0.10 −0.15 RJ |
See also
editReferences
edit- ^ a b c "KELT-1". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-01-18.
- ^ a b c d e f g h Siverd, Robert J.; Beatty, Thomas G.; Pepper, Joshua; Eastman, Jason D.; Collins, Karen; Bieryla, Allyson; Latham, David W.; Buchhave, Lars A.; Jensen, Eric L. N.; Crepp, Justin R.; Street, Rachel; Stassun, Keivan G.; Scott Gaudi, B.; Berlind, Perry; Calkins, Michael L.; Depoy, D. L.; Esquerdo, Gilbert A.; Fulton, Benjamin J.; Fűrész, Gábor; Geary, John C.; Gould, Andrew; Hebb, Leslie; Kielkopf, John F.; Marshall, Jennifer L.; Pogge, Richard; Stanek, K. Z.; Stefanik, Robert P.; Szentgyorgyi, Andrew H.; Trueblood, Mark; et al. (2012), "KELT-1b: A STRONGLY IRRADIATED, HIGHLY INFLATED, SHORT PERIOD, 27 JUPITER-MASS COMPANION TRANSITING A MID-F STAR", The Astrophysical Journal, 761 (2): 123, arXiv:1206.1635, Bibcode:2012ApJ...761..123S, doi:10.1088/0004-637X/761/2/123, S2CID 118439102
- ^ a b c d Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
- ^ a b c Johns, Daniel; Marti, Connor; Huff, Madison; McCann, Jacob; Wittenmyer, Robert A.; Horner, Jonathan; Wright, Duncan J. (2018), "Revised Exoplanet Radii and Habitability Using Gaia Data Release 2", The Astrophysical Journal Supplement Series, 239 (1): 14, arXiv:1808.04533, Bibcode:2018ApJS..239...14J, doi:10.3847/1538-4365/aae5fb, S2CID 119503072
- ^ a b Beatty, Thomas G.; Wong, Ian; Fetherolf, Tara; Line, Michael R.; Shporer, Avi; Stassun, Keivan G.; Ricker, George R.; Seager, Sara; Winn, Joshua N.; Jenkins, Jon M.; Louie, Dana R.; Schlieder, Joshua E.; Sha, Lizhou; Tenenbaum, Peter; Yahalomi, Daniel A. (2020), "The TESS phase curve of KELT-1b suggests a high dayside albedo", The Astronomical Journal, 160 (5): 211, arXiv:2006.10292, Bibcode:2020AJ....160..211B, doi:10.3847/1538-3881/abb5aa, S2CID 219792029
- ^ Beatty, Thomas G.; Marley, Mark S.; Gaudi, B. Scott; Colón, Knicole D.; Fortney, Jonathan J.; Showman, Adam P. (2019), "Spitzer Phase Curves of KELT-1b and the Signatures of Nightside Clouds in Thermal Phase Observations", The Astronomical Journal, 158 (4): 166, arXiv:1808.09575, Bibcode:2019AJ....158..166B, doi:10.3847/1538-3881/ab33fc, S2CID 119055976
- ^ a b Maciejewski, G.; Fernández, M.; Aceituno, F.; Martín-Ruiz, S.; Ohlert, J.; Dimitrov, D.; Szyszka, K.; von Essen, C.; Mugrauer, M.; Bischoff, R.; Michel, K. -U.; Mallonn, M.; Stangret, M.; Moździerski, D. (2018), "Planet-star interactions with precise transit timing. I. The refined orbital decay rate for WASP-12 b and initial constraints for HAT-P-23 b, KELT-1 b, KELT-16 b, WASP-33 b, and WASP-103 b", Acta Astronomica, 68 (4): 371, arXiv:1812.02438, Bibcode:2018AcA....68..371M, doi:10.32023/0001-5237/68.4.4, S2CID 118895482