Gliese 667
| Gliese 667 A | |
| Stellar characteristics | |
|---|---|
| Constellation | Scorpius |
| Right ascension (Epoch J2000) | 17h 18m 57.18s |
| Declination (Epoch J2000) | −34° 59' 23.3" |
| Spectral type | K3V |
| Distance from Sol | 22.74 ly |
| Other designations | HR 6426, Gl 667 A, Hip 84709, HD 156384, CD-34 11626 A, CP-34 6803, SAO 208670, LHS 442, LTT 6888, LFT 1336, LPM 638, UGPMF 433, MLO 4A. |
| Gliese 667 B | |
| Stellar characteristics | |
|---|---|
| Constellation | Scorpius |
| Right ascension (Epoch J2000) | 17h 18m 57.18s |
| Declination (Epoch J2000) | −34° 59' 23.3" |
| Spectral type | K5 V |
| Distance from Sol | 22.74 ly |
| Other designations | Gl 667 B, MLO 4B. |
| Gliese 667 C | |
| 250px Gliese 667 Cc, in the Gliese 667 C system | |
| Stellar characteristics | |
|---|---|
| Constellation | Scorpius |
| Right ascension (Epoch J2000) | 17h 18m 57.18s |
| Declination (Epoch J2000) | −34° 59' 23.3" |
| Spectral type | M1.5-2.5 V |
| Distance from Sol | 22.74 ly |
| Other designations | Gl 667 C, LHS 443, MLO 4C. |
| Planets | Gliese 667 Cb Gliese 667 Cc possibly two others |
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. There is a 12th magnitude star close to the other three, but it is not gravitationally bound to the 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".
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.
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.
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.
Gliese 667 C has at least two known companions, Gliese 667 Cb and Gliese 667 Cc, and may have at least two more companions.
Gliese 667 Cb
Gliese 667 Cb is an extrasolar planet which orbits the M-type main sequence star Gliese 667 C, located approximately 23 light years away in the constellation Scorpius. This planet has at least 5.7 times the mass of Earth (classifying as super-Earth) and takes a week to orbit the star at a semimajor axis of approximately 0.05 AU. However unlike most other known exoplanets, its eccentricity is not known, but it is typical that its inclination is not known. This planet was detected by HARPS on October 19, 2009
(Data from WikiPedia)
Gliese 667 Cc
An earthlike planet with an orbital period of about 28 days and a minimum mass 4.5 times that of the Earth, in the Gliese 667 C goldilocks zone. See http://news.ucsc.edu/2012/02/habitable-planet.html for details.
