Gliese 754
Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Telescopium |
Right ascension | 19h 20m 47.98349s[1] |
Declination | −45° 33′ 29.6292″[1] |
Apparent magnitude (V) | 12.25[2] |
Characteristics | |
Spectral type | M4V[2] |
Astrometry | |
Radial velocity (Rv) | +6.8[3] km/s |
Proper motion (μ) | RA: +659.330[1] mas/yr Dec.: −2,897.035[1] mas/yr |
Parallax (π) | 169.2351 ± 0.0588[4] mas |
Distance | 19.272 ± 0.007 ly (5.909 ± 0.002 pc) |
Details[3] | |
Mass | 0.173 M☉ |
Radius | 0.205 R☉ |
Luminosity | 0.005[5] L☉ |
Temperature | 3,202±100[6] K |
Metallicity [Fe/H] | −0.169[6] dex |
Rotation | 132.651 days |
Other designations | |
Database references | |
SIMBAD | data |
Gliese 754 is a dim star in the southern constellation of Telescopium. It has an apparent visual magnitude of 12.25,[2] which requires a telescope to view. The star is located at a distance of 19.3 light-years from the Sun based on parallax,[1] and it is drifting further away with a radial velocity of +7 km/s.[3] It is one of the hundred closest stars to the Solar System. Calculations of its orbit around the Milky Way showed that it is eccentric, and indicate that it might be a thick disk object.[8]
The stellar classification of Gliese 754 is M4V,[2] indicating that this is a small red dwarf star on the core hydrogen fusing main sequence. It has 17% of the mass of the Sun and 21% of the Sun's radius.[3] The star is fully convective and is a source of X-ray emission.[9] It is rotating slowly with a period of about 133 days.[3] The metallicity is sub-solar,[6] indicating it has a lower abundance of heavy elements compared to the Sun. It is radiating just 0.5%[5] of the luminosity of the Sun from its photosphere at an effective temperature of around 3,202 K.[6]
Planetary System[]
In June 2019 a candidate exoplanet was reported in orbit around Gliese 754. It was detected using the Doppler method and is orbiting at a distance of 0.28 AU with a period of 78 days. The orbit is essentially circular, to within the margin of error.[10] The habitable zone for this star ranges from 0.05 AU to 0.14 AU;[5] inside the orbit of this proposed companion.
Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b (unconfirmed) | ≥9.8+4.6 −5.2 M |