Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Virgo |
Right ascension | 12h 13m 53.3962s [1] |
Declination | −00° 23′ 36.5534″ [1] |
Apparent magnitude (V) | 8.951 [2] |
Characteristics | |
Evolutionary stage | Main sequence |
Spectral type | F5V [3] |
B−V color index | 0.45 [2] |
Astrometry | |
Radial velocity (Rv) | −3.2±0.3 [1] km/s |
Proper motion (μ) |
RA: −2.36±0.03
mas/
yr
[1] Dec.: 11.943±0.019 mas/ yr [1] |
Parallax (π) | 9.1725 ± 0.0221 mas [1] |
Distance | 355.6 ± 0.9
ly (109.0 ± 0.3 pc) |
Details | |
Mass | 1.105+0.028 −0.036 [4] M☉ |
Radius | 1.286+0.049 −0.040 [4] R☉ |
Luminosity | 2.432+0.057 −0.234 [4] L☉ |
Surface gravity (log g) | 4.261+0.027 −0.024 [4] cgs |
Temperature | 6,300±37 [4] K |
Metallicity [Fe/H] | −0.268+0.060 −0.071 [4] dex |
Rotation | 4.78±0.15 [5] |
Rotational velocity (v sin i) | 12.9±0.4 [4] km/s |
Age | 3.987+0.802 −0.516 [4] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
HD 106315, or K2-109, is a single star with a pair of close-orbiting exoplanets, located in the constellation of Virgo. Based on parallax measurements, this system lies at a distance of 356 light years from the Sun. [1] At that range, the star is too faint to be seen with the naked eye, as it has an apparent visual magnitude of 8.95. [2] But it is slowly drifting closer with a radial velocity of −3 km/s. [1] As of 2020 [update], multiplicity surveys have not detected any stellar companions to HD 106315. [5]
The spectrum of HD 106315 presents as an ordinary F-type main-sequence star with a stellar classification of F5V, [3] indicating it is generating energy through hydrogen fusion at its core. It is estimated to be roughly four [4] billion years old but is spinning quickly with a rotation period of 5 days. The star is relatively metal-poor, having 60% of solar concentration of iron. It has only a low level of magnetic activity in its chromosphere, showing a minimal level of star spot coverage. [5] The star has 11% more mass and a 29% larger radius than the Sun. It is radiating 2.4 times the luminosity of the Sun from its photosphere at an effective temperature of 6,300 K. [4]
Two planets were detected by the
transit method in 2017,
[4] using data from the extended
Kepler mission (K2). Their large planetary radii imply both planets have a massive steam atmosphere for planet
b and hydrogen-helium atmosphere for planet
c.
[5] The planetary system of HD 106315 is rather unstable and current planetary orbits are the outcome of violent dynamical history,
[7] strongly affected by relativistic effects.
[8] The orbits of planets are nearly coplanar, and orbit of
c is well aligned with the equatorial plane of the star, misalignment been equal to -10+3.6
−3.8°.
[9]
Since 2017, a third outer planet with mass above 45ME is suspected to exist in the system. [2]
Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | 10.5±3.1 [5] M🜨 | 0.0924+0.0011 −0.0012 |
9.55288±0.00021 | 0 | 87.6+3.0 −1.7 ° |
2.4±0.2 R🜨 |
c | 12.0±3.8 [5] M🜨 | 0.1565+0.0019 −0.0020 |
21.05652±0.00012 | 0 | 88.89+0.69 −0.51 ° |
4.379±0.086 R🜨 |
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Virgo |
Right ascension | 12h 13m 53.3962s [1] |
Declination | −00° 23′ 36.5534″ [1] |
Apparent magnitude (V) | 8.951 [2] |
Characteristics | |
Evolutionary stage | Main sequence |
Spectral type | F5V [3] |
B−V color index | 0.45 [2] |
Astrometry | |
Radial velocity (Rv) | −3.2±0.3 [1] km/s |
Proper motion (μ) |
RA: −2.36±0.03
mas/
yr
[1] Dec.: 11.943±0.019 mas/ yr [1] |
Parallax (π) | 9.1725 ± 0.0221 mas [1] |
Distance | 355.6 ± 0.9
ly (109.0 ± 0.3 pc) |
Details | |
Mass | 1.105+0.028 −0.036 [4] M☉ |
Radius | 1.286+0.049 −0.040 [4] R☉ |
Luminosity | 2.432+0.057 −0.234 [4] L☉ |
Surface gravity (log g) | 4.261+0.027 −0.024 [4] cgs |
Temperature | 6,300±37 [4] K |
Metallicity [Fe/H] | −0.268+0.060 −0.071 [4] dex |
Rotation | 4.78±0.15 [5] |
Rotational velocity (v sin i) | 12.9±0.4 [4] km/s |
Age | 3.987+0.802 −0.516 [4] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
HD 106315, or K2-109, is a single star with a pair of close-orbiting exoplanets, located in the constellation of Virgo. Based on parallax measurements, this system lies at a distance of 356 light years from the Sun. [1] At that range, the star is too faint to be seen with the naked eye, as it has an apparent visual magnitude of 8.95. [2] But it is slowly drifting closer with a radial velocity of −3 km/s. [1] As of 2020 [update], multiplicity surveys have not detected any stellar companions to HD 106315. [5]
The spectrum of HD 106315 presents as an ordinary F-type main-sequence star with a stellar classification of F5V, [3] indicating it is generating energy through hydrogen fusion at its core. It is estimated to be roughly four [4] billion years old but is spinning quickly with a rotation period of 5 days. The star is relatively metal-poor, having 60% of solar concentration of iron. It has only a low level of magnetic activity in its chromosphere, showing a minimal level of star spot coverage. [5] The star has 11% more mass and a 29% larger radius than the Sun. It is radiating 2.4 times the luminosity of the Sun from its photosphere at an effective temperature of 6,300 K. [4]
Two planets were detected by the
transit method in 2017,
[4] using data from the extended
Kepler mission (K2). Their large planetary radii imply both planets have a massive steam atmosphere for planet
b and hydrogen-helium atmosphere for planet
c.
[5] The planetary system of HD 106315 is rather unstable and current planetary orbits are the outcome of violent dynamical history,
[7] strongly affected by relativistic effects.
[8] The orbits of planets are nearly coplanar, and orbit of
c is well aligned with the equatorial plane of the star, misalignment been equal to -10+3.6
−3.8°.
[9]
Since 2017, a third outer planet with mass above 45ME is suspected to exist in the system. [2]
Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | 10.5±3.1 [5] M🜨 | 0.0924+0.0011 −0.0012 |
9.55288±0.00021 | 0 | 87.6+3.0 −1.7 ° |
2.4±0.2 R🜨 |
c | 12.0±3.8 [5] M🜨 | 0.1565+0.0019 −0.0020 |
21.05652±0.00012 | 0 | 88.89+0.69 −0.51 ° |
4.379±0.086 R🜨 |