Holland 667

Database links to Gliese 667

Triple star Gliese 667
Image of the sky around Gliese 667
Observation data epoch : J2000.0
AladinLite
Constellation	Scorpio
Vis. Brightness (total)	5.91 likes
Known exoplanets	6th
Astrometry
Radial velocity	6.5 km / s
parallax	140.88 ± 2.04 mas
distance	23.2 ± 0.3 ly (7.1 ± 0.1 pc )
Age	2-10 billion a
Proper movement
Rec. Share:	1129.76 mas / a
Dec. portion:	−77.02 mas / a
Individual data
Names	A, B, C
Observation data:
Right ascension	A.	17 h 18 m 56.415 s
	B.	17 h 18 m 56.247 s
	C.	17 h 18 m 58.827 s
declination	A.	−34 ° 59 ′ 22,482 ″
	B.	−34 ° 59 ′ 22,237 ″
	C.	−34 ° 59 ′ 48,613 ″
Apparent brightness	A.	6.37 m
	B.	7.38 m
	C.	10.22 m
Typing:
Spectral class	A.	K3 V
	B.	K5 V
	C.	M1.5 V
BV color index	A.	+1.15
	B.	+1.44
	C.	+1.57
UB color index	A.
	B.
	C.	+1.17
Astrometry:
rel. Brightness (G-band)	A.	like
	B.	like
	C.	9.38 likes
Absolute visual brightness M vis	A.	7.07 likes
	B.	8.02 mag
	C.	11.03 mag
Physical Properties:
Dimensions	A.	0.73 M ☉
	B.	0.69 M ☉
	C.	0.31 M ☉
radius	A.	0.76 R ☉
	B.	0.70 R ☉
	C.	0.42 R ☉
Luminosity	A.	L ☉
	B.	L ☉
	C.	0.0137 L ☉
Effective temperature	A.	K
	B.	K
	C.	3,700 ± 100 K
Metallicity [Fe / H]	A.
	B.
	C.	-0.59 ± 0.10
Rotation time	A.	d
	B.	d
	C.	105 d
Designations and catalog entries
Bright Star Cat.	HR 6426
HD catalog	HD 156384
SAO catalog	SAO 208670
Hipparcos catalog	HIP 84709
WDS catalog	WDS 17190-3459
Tycho catalog	A.	TYC 7370-850-1
	B.	TYC 7370-850-2
	C.	TYC

Gliese 667 (abbreviated GJ 667 , also 142 G. Scorpii and HR 6426 ) is a triple star system in the constellation Scorpio , which is a little over 23 light years away from the sun . It consists of two orange luminous main sequence stars of the spectral class K (Gliese 667 A and B), which orbit each other once in 42 years, as well as a red dwarf of the spectral class M (Gliese 667 C), which orbits both further out. It has been known since 2009 that the third component, Gliese 667 C, has a planetary system .

With an apparent brightness of 5.91 mag, Gliese 667 is visible to the naked eye in a clear and moonless sky without light pollution as a very faint star northwest of Shaula (Lambda Scorpii) and Lesath (Ypsilon Scorpii).

Components

Gliese 667 A

Gliese 667 A has the spectral class K3 V and has 73% of the solar mass and 76% of the solar radius , but only about 12 to 13% of the luminosity of the sun. The measured metallicity for the Gliese 667 AB pair is −0.59, significantly lower than for the sun. Components A and B orbit each other in 42 years at an apparent distance of 1.8 arc seconds . They were recognized and recorded as double stars in the 19th century.

Gliese 667 B

Gliese 667 B has the spectral class K5 V and around 69% of the solar mass and 70% of the solar radius.

Gliese 667 C

Gliese 667 C has the spectral class M1.5 V and is at least 230 AU away from the Gliese 667 AB pair. As a faint red dwarf, it has only 31% of the mass or 42% of the radius of the sun and has only 1.4% of the luminosity of the sun.

Planetary system

Artist's impression of the surface of Gliese 667 Cc with a view of the three stars

On 19 October 2009, the discovery was an exoplanet around Gliese 667 C announced the discovery of the Échelle spectrograph HARPS of the ESO was made. According to the procedure for naming exoplanets, this was given the designation Gliese 667 Cb . The planet has a little more than five and a half times the mass of the earth and orbits its central star in around 7 days. It is the most massive member of the planetary system and can be classified as either super-earth or mini-Neptune .

Again based on measurement data from the HARPS instrument, the discovery of Gliese 667 Cc was published on November 21, 2011 . and announced on February 2, 2012 by researchers from the University of Göttingen and the Carnegie Institution for Science . The planet with about four times the mass of the earth orbits Gliese 667 C in about 28 days and is located in its habitable zone , where liquid water can exist on the planet's surface.

Gliese planetary system 667 Cc with the assumed six to seven planets (now refuted)

Further investigation and analysis of older data suggested the existence of up to four or five other planets, the discovery of which was published on June 25, 2013. They should complete an orbit around their central star in around 39 ( Gliese 667 Cf ), 62 ( Gliese 667 Ce ), 91 ( Gliese 667 Cd ) and 256 days ( Gliese 667 Cg ). According to this, Gliese 667 C would have been orbited by a total of six or seven planets, three of which are super-earths in the habitable zone (though very likely in bound rotation ).

The review of the data obtained by means of the radial velocity method showed in the same year that the supposedly existing planets can be traced back to disruptive effects. In 2014 only the existence of the two first discovered planets Gliese 667 Cb and Gliese 667 Cc could be confirmed.

A 2016 study finally confirmed most of the proposed planets.

Gliese planetary system 667 C

Planet (by distance from the star)	Discovery (year)	Mass (in M ⊕ )	Cycle time (in days)	Major semi-axis (in AU )	eccentricity
Gliese 667 Cb	2009	5.6	7.20	0.0505	0.13
Gliese 667 cc	2011	3.8	28.14	0.125	0.02
Gliese 667 Cd	2012	5.1	91.61	0.276	0.03
Gliese 667 Ce	2013	2.7	62.24	0.213	0.02
Gliese 667 Cf	2013	2.7	39.03	0.156	0.03
Gliese 667 Cg	2013	4.6	256.2	0.549	0.08

Web links

Commons : Gliese 667  - Collection of images, videos and audio files

• Open Exoplanet Catalog: Gliese 667. Retrieved May 5, 2015 .  (English)
• SolStation.com: MLO 4 / HR 6426 / Gl 667 ABC. Retrieved May 5, 2015 .  (English)

Individual evidence

1. ↑ The Hipparcos Main Catalog: HIP 84709. Retrieved May 5, 2015 . 
2. ↑ ^{a b c d e f g h i j k l} Anglada-Escudé, Guillem; Arriagada, Pamela; Vogt, Steven S .; Rivera, Eugenio J .; Butler, R. Paul; Crane, Jeffrey D .; Shectman, Stephen A .; Thompson, Ian B .; Minniti, Dante; Haghighipour, Nader ; Carter, Brad D .; Tinney, CG; Wittenmyer, Robert A .; Bailey, Jeremy A .; O'Toole, Simon J .; Jones, Hugh RA; Jenkins, James S .: A planetary system around the nearby M dwarf GJ 667C with at least one super-Earth in its habitable zone . arxiv : 1202.0446 .
3. ↑ Lurie, John C .; Henry, Todd J .; Jao, Wei-Chun; Quinn, Samuel N .; Winters, Jennifer G .; Ianna, Philip A .; Koerner, David W .; Riedel, Adric R .; Subasavage, John P .: The Solar Neighborhood. XXXIV. A Search for Planets Orbiting Nearby M Dwarfs using Astrometry . arxiv : 1407.4820 .
4. ^ Van Leeuwen, F .: Validation of the new Hipparcos reduction . arxiv : 0708.1752 .
5. ↑ HD 156384. In: SIMBAD . Center de Données astronomiques de Strasbourg , accessed on May 4, 2019 . 
6. ↑ ^{a b c} HD 156384A. In: SIMBAD. Center de Données astronomiques de Strasbourg, accessed on May 4, 2019 . 
7. ↑ ^{a b c} HD 156384B. In: SIMBAD. Center de Données astronomiques de Strasbourg, accessed on May 4, 2019 . 
8. ↑ ^{a b c d e} HD 156384C. In: SIMBAD. Center de Données astronomiques de Strasbourg, accessed on May 4, 2019 . 
9. ↑ ^{a b c d} Tokovinin, A .: Comparative statistics and origin of triple and quadruple stars . arxiv : 0806.3263 .
10. ↑ ^{a b c} Pasinetti Fracassini, LE et al .: Catalog of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third Edition - Comments and Statistics . arxiv : astro-ph / 0012289 .
11. ^ University of Oslo: Life on Gliese 667Cc? (No longer available online.) Archived from the original on July 3, 2013 ; Retrieved May 5, 2015 . Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.  
12. ^ European Southern Observatory: 32 New Exoplanets Found. Retrieved May 5, 2015 . 
13. ^ Bonfils, X. et al .: The HARPS search for southern extra-solar planets XXXI. The M-dwarf sample . arxiv : 1111.5019 .
14. ↑ Georg-August-Universität Göttingen: Press release: Scientists discover possibly habitable super-earth. Retrieved May 5, 2015 . 
15. ↑ Anglada-Escudé, Guillem; Tuomi, Mikko; Gerlach, Enrico; Barnes, Rory; Heller, René; Jenkins, James S .; Wende, Sebastian; Vogt, Steven S .; Butler, R. Paul; Reiners, Ansgar; Jones, Hugh RA: A dynamically-packed planetary system around GJ667C with three super-Earths in its habitable zone . arxiv : 1306.6074 .
16. ^ European Southern Observatory: Three Planets in Habitable Zone of Nearby Star. Retrieved May 5, 2015 . 
17. ↑ Feroz, Farhan; Hobson, Mike: Bayesian analysis of radial velocity data of GJ667C with correlated noise: evidence for only 2 planets . arxiv : 1307.6984 .
18. ^ Robertson, Paul; Mahadevan, Suvrath: Disentangling Planets and Stellar Activity for Gliese 667C . arxiv : 1409.0021 .
19. ↑ The Spin-Orbit Evolution of GJ 667C System: The Effect of Composition and Other Planet's Perturbations . arxiv : 1606.07546 .
20. ↑ Gliese 667 Cb. Accessed February 10, 2018 . 
21. ↑ Gliese 667 Cc. Retrieved February 10, 2018 . 
22. ↑ Gliese 667 Cd. Retrieved February 10, 2018 . 
23. ↑ Gliese 667 Ce. Retrieved February 10, 2018 . 
24. ↑ Gliese 667 cf. Retrieved February 10, 2018 . 
25. ↑ Gliese 667 Cg. Retrieved February 10, 2018 .