Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Virgo |
Right ascension | 13h 50m 37.4100s [1] |
Declination | −06° 48′ 14.4199″ [1] |
Apparent magnitude (V) | 13.3 [2] |
Characteristics | |
Spectral type | K5V [1] |
Astrometry | |
Radial velocity (Rv) | -23.55 km/s |
Proper motion (μ) | RA: -88.184 [1] mas/yr Dec.: -15.290 [1] mas/yr |
Parallax (π) | 5.4849 ± 0.0365 mas [3] |
Distance | 595 ± 4 ly (182 ± 1 pc) |
Details [4] [2] | |
Mass | 0.727±0.024 M☉ |
Radius | 0.7033±0.0080 R☉ |
Surface gravity (log g) | 4.601±0.018 cgs |
Temperature | 4645±50 K |
Metallicity [Fe/H] | 0.13±0.1 [5] dex |
Rotation | 18.0±0.2 |
Rotational velocity (v sin i) | 2.0±0.2 km/s |
Age | 9 Gyr |
Other designations | |
Database references | |
SIMBAD | data |
Qatar-2 is a K-type main-sequence star about 595 light-years away in the constellation of Virgo. The star is much older than Sun, and has a concentration of heavy elements similar to solar abundance. [2] The star features a numerous and long-lived starspots, [4] and belongs to a peculiar variety of inflated K-dwarfs with strong magnetic activity inhibiting internal convection. [6]
In 2011 a transiting superjovian planet Qatar-2b was detected by the Qatar Exoplanet Survey. [2] The planet has a large measured temperature difference between dayside (1368±32 K) and nightside (724±135 K). [7] The planetary orbit is well aligned with the equatorial plane of the star, [5] misalignment angle equal to 4.3±4.5◦. [8] No orbital decay was detected. [9] The color of planetary atmosphere is blue due to Rayleigh scattering of light, [8] and albedo is very low, being below 0.06. [9]
An additional massive companion on wide orbit was suspected in 2011, [2] but search utilizing transit-timing variation method has yielded zero results in 2017. [4]
Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | 2.466±0.062 MJ | 0.02136±0.00024 | 1.33711677±0.00000010 | 0 | 88.99±0.20° | 1.115±0.013 RJ |
WASP-6, also officially named Márohu, is a type-G yellow dwarf star located about 600 light-years away in the Aquarius constellation. Dim at magnitude 12, it is visible through a moderate sized amateur telescope. The star is about 80% of the size and mass of the Sun and it is a little cooler. Starspots in the WASP-6 system helped to refine the measurements of the mass and the radius of the planet WASP-6b.
WASP-8 is a binary star system 294 light-years away. The star system is much younger than the Sun at 300 million to 1.2 billion years age, and is heavily enriched in heavy elements, having nearly twice the concentration of iron compared to the Sun.
WASP-10 is a star in the constellation Pegasus. The SuperWASP project has observed and classified this star as a variable star, perhaps due to the eclipsing planet.
HAT-P-11, also designated GSC 03561-02092 and Kepler-3, is an orange dwarf metal rich star about 123 light-years away in the constellation Cygnus. This star is notable for its relatively large rate of proper motion. The magnitude of this star is about 9, which means it is not visible to the naked eye but can be seen with a medium-sized amateur telescope on a clear dark night. The age of this star is about 6.5 billion years.
WASP-26 is a yellow main sequence star in the constellation of Cetus.
Qatar-1 is an orange main sequence star in the constellation of Draco.
WASP-50 is a G-type main-sequence star about 610 light-years away. The star is older than the Sun and slightly depleted in heavy elements compared to the Sun, and has a close to average starspot activity. Despite its advanced age, the star is rotating rapidly, being spun up by the tides raised by giant planet on close orbit.
WASP-48 is a subgiant star about 1400 light-years away. The star is likely older than Sun and slightly depleted in heavy elements. It shows an infrared excess noise of unknown origin, yet has no detectable ultraviolet emissions associated with the starspot activity. The discrepancy may be due to large interstellar absorption of light in interstellar medium for WASP-48. The measurements are compounded by the emission from eclipsing contact binary NSVS-3071474 projected on sky plane nearby, although no true stellar companions were detected by survey in 2015.
WASP-46 is a G-type main-sequence star about 1,210 light-years away. The star is older than the Sun and is strongly depleted in heavy elements compared to the Sun, having just 45% of the solar abundance. Despite its advanced age, the star is rotating rapidly, being spun up by the tides raised by a giant planet on a close orbit.
GSC 03949-00967 is a G-type main-sequence star about 1190 light-years away. It is older than the Sun, yet is enriched by heavy elements compared to the Sun, having 160% of solar abundance.
WASP-72 is the primary of a binary star system. It is an F7 class dwarf star, with an internal structure just on the verge of the Kraft break. It is orbited by a planet WASP-72b. The age of WASP-72 is younger than the Sun at 3.55±0.82 billion years.
BD+00 316 is an ordinary star with a close-orbiting planetary companion in the equatorial constellation of Cetus. It is also known as WASP-71 since 2019; BD+00 316 is the stellar identifier from the Bonner Durchmusterung catalogue. With an apparent visual magnitude of 10.56, it is too faint to be visible to the naked eye. This star is located at a distance of 1,160 light-years based on parallax measurements, and is drifting further away with a heliocentric radial velocity of 7.7 km/s.
WASP-64 is a star about 1200 light-years away. It is a G7 class main-sequence star, orbited by a planet WASP-64b. It is younger than the Sun at 3.6±1.6 billion years, and it has a metal abundance similar to the Sun. The star is rotating rapidly, being spun up by the giant planet in a close orbit.
WASP-60 is a F-type main-sequence star about 1420 light-years away. The stars age is much younger than the Sun's at 1.7±0.5 billion years. WASP-60 is enriched in heavy elements, having 180% of the solar abundance of iron. The star does not have noticeable starspot activity, an unexpected observation for a relatively young star. The age of WASP-60 determined by different methods is highly discrepant though, and it may actually be an old star which experienced an episode of spin-up in the past.
WASP-52 is a K-type main-sequence star about 570 light-years away. It is older than the Sun at 10.7+1.9
−4.5 billion years, but it has a similar fraction of heavy elements. The star has prominent starspot activity, with 3% to 14% of the stellar surface covered by areas 575±150 K cooler than the rest of the photosphere.
WASP-41 is a G-type main-sequence star. Its surface temperature is 5450±150 K. WASP-41 is similar to the Sun in its concentration of heavy elements, with a metallicity Fe/H index of −0.080±0.090, but is much younger at an age of 2.289±0.077 billion years. The star does exhibit strong starspot activity, with spots covering 3% of the stellar surface.
WASP-69, also named Wouri, is a K-type main-sequence star 164 light-years away. Its surface temperature is 4782±15 K. WASP-69 is slightly enriched in heavy elements compared to the Sun, with a metallicity Fe/H index of 0.10±0.01, and is much younger than the Sun at 2 billion years. The data regarding starspot activity of WASP-69 are inconclusive, but spot coverage of the photosphere may be very high.
WASP-88 is a F-type main-sequence star. Its surface temperature is 6450±61 K. WASP-88 is similar to the Sun in its concentration of heavy elements, with a metallicity Fe/H index of 0.03±0.04, and is younger at an age of 3.0±1.3 billion years.
WASP-84, also known as BD+02 2056, is a G-type main-sequence star 327 light-years away in the constellation Hydra. Its surface temperature is 5350±31 K and is slightly enriched in heavy elements compared to the Sun, with a metallicity Fe/H index of 0.05±0.02. It is rich in carbon and depleted of oxygen. WASP-84's age is probably older than the Sun at 8.5+4.1
−5.5 billion years. The star appears to have an anomalously small radius, which can be explained by the unusually high helium fraction or by it being very young.
WASP-80 is a K-type main-sequence star about 162 light-years away. The star's age is much younger than the Sun's at 1.352±0.222 billion years. WASP-80 is similar to the Sun in concentration of heavy elements, although this measurement is highly uncertain.