Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Virgo |
Right ascension | 14h 51m 04.1870s [1] |
Declination | +05° 56′ 50.549″ [1] |
Apparent magnitude (V) | 12.214 [2] |
Characteristics | |
Evolutionary stage | main-sequence star |
Spectral type | G8 |
Astrometry | |
Radial velocity (Rv) | -15.901 [3] km/s |
Proper motion (μ) |
RA: −28.610(19)
mas/
yr
[1] Dec.: −2.774(19) mas/ yr [1] |
Parallax (π) | 4.952 ± 0.0169 mas [1] |
Distance | 659 ± 2
ly (201.9 ± 0.7 pc) |
Orbit [4] | |
Primary | HAT-P-27 |
Companion | HAT-P-27 B |
Semi-major axis (a) | 0.656±0.021" (131 AU) |
Details [2] | |
Mass | 0.945±0.035 M☉ |
Radius | 0.898+0.054 −0.039 R☉ |
Luminosity | 0.57+0.09 −0.07 L☉ |
Surface gravity (log g) | 4.51±0.04 cgs |
Temperature | 5300±90 K |
Metallicity [Fe/H] | 0.29±0.10 dex |
Rotation | 0.4±0.4 |
Rotational velocity (v sin i) | 0.6+0.7 −0.4 [5] km/s |
Age | 4.4+3.8 −2.6 Gyr |
Other designations | |
Database references | |
SIMBAD | data |
HAT-P-27, also known as WASP-40, is the primary of a binary star system about 659 light-years away. It is a G-type main-sequence star. The star's age is similar to the Sun's at 4.4 billion years. [2] HAT-P-27 is enriched in heavy elements, having a 195% concentration of iron compared to the Sun.
The very dim stellar companion was detected in 2015 at a projected separation of 0.656″ [4] and proven to be physically bound to the system in 2016. [6]
In 2011 a transiting hot Jupiter type planet b was detected in a mildly eccentric orbit. The planetary equilibrium temperature is 1207±41 K. [2] The survey in 2013 failed to find any Rossiter-McLaughlin effect and therefore was unable to constrain the inclination of planetary orbit to the equatorial plane of the parent star. [5] No orbital decay was detected as in 2018, despite the close proximity of the planet to the star. [7]
The presence of an additional planet in the system has been suspected since 2015. [8]
Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | 0.660±0.033 MJ | 0.0403±0.0005 | 3.039586±0.000012 | 0.078±0.047 | 85.0±0.2 [5] ° | 1.038+0.077 −0.058 RJ |
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Virgo |
Right ascension | 14h 51m 04.1870s [1] |
Declination | +05° 56′ 50.549″ [1] |
Apparent magnitude (V) | 12.214 [2] |
Characteristics | |
Evolutionary stage | main-sequence star |
Spectral type | G8 |
Astrometry | |
Radial velocity (Rv) | -15.901 [3] km/s |
Proper motion (μ) |
RA: −28.610(19)
mas/
yr
[1] Dec.: −2.774(19) mas/ yr [1] |
Parallax (π) | 4.952 ± 0.0169 mas [1] |
Distance | 659 ± 2
ly (201.9 ± 0.7 pc) |
Orbit [4] | |
Primary | HAT-P-27 |
Companion | HAT-P-27 B |
Semi-major axis (a) | 0.656±0.021" (131 AU) |
Details [2] | |
Mass | 0.945±0.035 M☉ |
Radius | 0.898+0.054 −0.039 R☉ |
Luminosity | 0.57+0.09 −0.07 L☉ |
Surface gravity (log g) | 4.51±0.04 cgs |
Temperature | 5300±90 K |
Metallicity [Fe/H] | 0.29±0.10 dex |
Rotation | 0.4±0.4 |
Rotational velocity (v sin i) | 0.6+0.7 −0.4 [5] km/s |
Age | 4.4+3.8 −2.6 Gyr |
Other designations | |
Database references | |
SIMBAD | data |
HAT-P-27, also known as WASP-40, is the primary of a binary star system about 659 light-years away. It is a G-type main-sequence star. The star's age is similar to the Sun's at 4.4 billion years. [2] HAT-P-27 is enriched in heavy elements, having a 195% concentration of iron compared to the Sun.
The very dim stellar companion was detected in 2015 at a projected separation of 0.656″ [4] and proven to be physically bound to the system in 2016. [6]
In 2011 a transiting hot Jupiter type planet b was detected in a mildly eccentric orbit. The planetary equilibrium temperature is 1207±41 K. [2] The survey in 2013 failed to find any Rossiter-McLaughlin effect and therefore was unable to constrain the inclination of planetary orbit to the equatorial plane of the parent star. [5] No orbital decay was detected as in 2018, despite the close proximity of the planet to the star. [7]
The presence of an additional planet in the system has been suspected since 2015. [8]
Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | 0.660±0.033 MJ | 0.0403±0.0005 | 3.039586±0.000012 | 0.078±0.047 | 85.0±0.2 [5] ° | 1.038+0.077 −0.058 RJ |