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 | |
Database references | |
SIMBAD | data |
Qatar-1 is an orange main sequence star in the constellation of Draco.
Qatar-1 has an average to high metallicity of 160% of solar,[1] and is of similar age to Sun.[2] The star has significant starspot activity.[4]
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 |