Qatar-1
Star in the constellation Draco
From Wikipedia, the free encyclopedia
Qatar-1 is an orange main sequence star in the constellation of Draco.
| Observation data Epoch J2000 Equinox | |
|---|---|
| Constellation | Draco |
| Right ascension | 20h 13m 31.6176s |
| Declination | 65° 09′ 43.4909″ |
| Apparent magnitude (V) | 12.84 |
| Characteristics | |
| Evolutionary stage | main sequence star |
| Spectral type | K3V |
| B−V color index | 1.06 |
| V−R color index | 0.19 |
| J−H color index | 0.472 |
| J−K color index | 0.590 |
| Variable type | planetary transit variable |
| Astrometry | |
| Radial velocity (Rv) | -37.835±0.063 km/s |
| Proper motion (μ) | RA: 12.636±0.048 mas/yr Dec.: 58.170±0.041 mas/yr |
| Parallax (π) | 5.3587±0.0231 mas |
| Distance | 609 ± 3 ly (186.6 ± 0.8 pc) |
| Details[1][2] | |
| Mass | 0.85±0.03 M☉ |
| Radius | 0.823±0.025 R☉ |
| Surface gravity (log g) | 4.536±0.024 cgs |
| Temperature | 4861±125 K |
| Metallicity [Fe/H] | 0.2±0.1 dex |
| Rotational velocity (v sin i) | 1.7±0.3 km/s |
| Age | 4.5 Gyr |
| Other designations | |
| Qatar-1, 2MASS J20133160+6509433, Gaia DR2 2244830490514284928, V592 Dra[3] | |
| Database references | |
| SIMBAD | data |
Star characteristics
Planetary system
The "Hot Jupiter" class planet Qatar-1b was discovered by the Qatar Exoplanet Survey in 2010.[1] The planetary orbit is likely aligned with the rotational axis of the star, with the misalignment measurement based on the Rossiter-McLaughlin effect equal to −8.4±7.1 degrees.[2] The planet has a large measured temperature difference between dayside (1696±39 K) and nightside (1098±158 K).[5] A spectroscopic study in 2017 does suggest that Qatar-1b has relatively clear skies with a few clouds.[6]
Additional planets or a brown dwarf in the system were suspected in 2013,[7] but were refuted in 2015.[8][9]
The transit-timing variation search in 2020 has also resulted in no detection of additional planets in the system,[10][11] although by 2022 additional transit-timing variation data have suggested the planetary system is accelerating under influence of the unseen long-period companion.[12]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 1.33±0.05 MJ | 0.02343±0.0012 | 1.4200236±0.0000001[11] | 0.020+0.011 −0.01 |
84.23±0.06° | 1.19±0.09 RJ |
