Gliese 667
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| Observation data Equinox J2000 |
|
|---|---|
| Constellation | Scorpius |
| Right ascension | 17h 18m 57.18s |
| Declination | −34° 59' 23.3" |
| Apparent magnitude (V) | 6.29/7.24/10.25 |
| Characteristics | |
| Spectral type | K6V / K5V / M2V |
| U-B color index | 0.83/???/1.17 |
| B-V color index | 1.03/???/1.57 |
| Variable type | A: suspected B: unknown C: flare star |
| Astrometry | |
| Radial velocity (Rv) | 0 km/s |
| Proper motion (μ) | RA: 1149.24 mas/yr Dec.: -90.80 mas/yr |
| Parallax (π) | 143.45 ± 17.12 mas |
| Distance | approx. 23 ly (approx. 7 pc) |
| Absolute magnitude (MV) | 7.07/8.02/11.03 |
| Details | |
| Mass | 0.75/0.65/0.38 M☉ |
| Radius | 0.77/0.44/0.20 R☉ |
| Luminosity | 0.13/0.05/0.003 L☉ |
| Temperature | 3950 K |
| Metallicity | 26% Sun |
| Rotation | |
| Age | years |
| Visual binary orbit | |
| Companion | Gliese 667 AB |
| Period (P) | 42.15 a |
| Semimajor axis (a) | 1.81" |
| Eccentricity (e) | 0.58 |
| Inclination (i) | 128° |
| Node (Ω) | 313° |
| Periastron epoch (T) | 1975.9 |
| Other designations | |
Gliese 667 (also HR 6426 and MLO 4) is a triple star system in the constellation of Scorpius. The star system lies at a distance of about 6.97 pc (22.7 ly). In addition to the three gravitationally bound stars, there is a fourth close component, but the 4th component is not bound to the system. To the naked eye, the system appears to be a single faint star of magnitude 5.89.
Contents |
[edit] The overall system
The two brightest components, Gl 667 A and Gl 667 B, are separated by an average distance of about 12.6 AU, but have an eccentric orbit, which takes them as close as about 5 AU, or as far as 20 AU. The orbit takes approximately 42.15 years to complete. The orbital distance translates to an average separation of 1.8".
Gl 667 C orbits further out, between about 56 and 215 AU, equating to an angular separation of about 30".
There is a 12th magnitude star close to the other three, but it is not gravitationally bound to the system.
The system has a relatively high proper motion, exceeding 1 second of arc per year.
[edit] Gliese 667 A
Gliese 667 A is an orange dwarf star of spectral class K3V. The star has a lower concentration of heavy elements (metals) than the Sun. The star has a mass of around 75% of that of the Sun and a luminosity of around 12 or 13% of that of the Sun. The apparent magnitude is 6.29, giving an absolute magnitude of around 7.07.
[edit] Gliese 667 B
Gliese 667 B is an orange dwarf star of spectral class K5V, with a mass of about 65% of that of the Sun, and only about 5% of the Sun's luminosity. The apparent magnitude is 7.24, giving an absolute magnitude of around 8.02.
[edit] Gliese 667 C
Gliese 667 C is a red dwarf star of spectral class of M2V. It has a mass of around 38% of that of the Sun and only 0.3% of the Sun's luminosity. The apparent magnitude is 10.25, giving an absolute magnitude of around 11.03.
