HD 154088
Observation data Epoch J2000.0 Equinox J2000.0 |
|
---|---|
Constellation | Ophiuchus |
Right ascension | 17h 04m 27.84s ± 5.62[1] |
Declination | −28° 34′ 57.64″ ± 3.16[1] |
Apparent magnitude (V) | 6.7258 ± 0.005[1] |
Characteristics | |
Spectral type | K0V |
B−V color index | 0.814 ± 0.034[1] |
Astrometry | |
Radial velocity (Rv) | 14.2972 ± 0.0003[2] km/s |
Proper motion (μ) | RA: 83.76 ± 0.64[1] mas/yr Dec.: -268.69 ± 0.36[1] mas/yr |
Parallax (π) | 56.06 ± 0.50[1] mas |
Distance | 58.2 ± 0.5 ly (17.8 ± 0.2 pc) |
Absolute magnitude (MV) | 5.47 ± 0.02[3] |
Details | |
Mass | 0.97 ± 0.05[4] M☉ |
Radius | 0.95 ± 0.03[5] R☉ |
Luminosity | 0.68 +0.06 −0.05 (log -0.169 ± 0.033)[6] L☉ |
Surface gravity (log g) | 4.40 ± 0.11[4] cgs |
Temperature | 5423 ± 51[4] K |
Metallicity [Fe/H] | 0.31 ± 0.03[4] dex |
Rotation | 42.6 ± 4.4[7] |
Rotational velocity (v sin i) | 1.9 ± 0.5[6] km/s |
Age | 3 - 8[4] Gyr |
Other designations | |
HIP 83541, Gliese 652
|
|
Database references | |
SIMBAD | data |
Extrasolar Planets Encyclopaedia |
data |
HD 154088 is a seventh magnitude metal-rich K-type main sequence star that lies approximately 58 light-years away in the constellation of Ophiuchus. The star is orbited by a hot Super-Earth.
Properties
HD 154088 is a modestly bright star that lies at the bottom of Ophiuchus, near to the border with Scorpius and near to the plane of the Milky Way. The star was recognised as a high proper motion star during the last century, and early Earth-based parallax measurements such as that of the Gliese Catalogue of Nearby Stars indicated a distance of about 50 light-years.
The star has a spectral type of K0V, indicating that it is a main sequence star that is about 350 degrees cooler than the Sun. On the Hertzsprung-Russell diagram (left), the star lies slightly above the main sequence. This is because the star is very metal-rich; with an Fe/H of 0.3 dex the star has about twice the solar abundance of iron, which makes HD 154088 fall into the somewhat vague group of super metal-rich (SMR) stars. The giant planet occurrence rate of Fe/H = 0.3 stars is on the order of 30%, but HD 154088 is not currently known to host any giant planets.
HD 154088 has a pronounced magnetic field.[4] It also has a magnetic cycle similar to the Sun,[7] though its length is not well constrained.
Planetary system
A planet orbiting HD 154088 discovered with the HARPS spectrograph was announced in September 2011. With a minimum mass of 6 Earth masses, the companion falls into the regime of Super-Earths.
Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | ≥6.15 ± 0.86 M⊕ | 0.1316 ± 0.0021 | 18.596 ± 0.021 | 0.38 ± 0.15 | — | — |
HD 154088 is also being observed under the Keck Eta-Earth radial velocity survey.[8] HD 154088 b is a close match for planet candidate 1 (orbital period = 18.1 days, minimum mass = 6.5 M⊕), so they may be the same detection.
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 2.0 2.1 2.2 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 3.0 3.1 The relevant calculation for absolute magnitude is , where is the apparent magnitude and is the distance in parsecs.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 5.0 5.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 6.0 6.1 6.2 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 7.0 7.1 7.2 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 8.0 8.1 Lua error in package.lua at line 80: module 'strict' not found.