Gliese 86

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Gliese 86
Observation data Epoch J2000.0 Equinox J2000.0
Constellation	Eridanus
Gliese 86 A
Right ascension	02^h 10^m 25.93^s^[1]
Declination	−50° 49′ 25.4″^[1]
Apparent magnitude (V)	6.17^[2]
Gliese 86 B
Right ascension	02^h 10^m 26^s
Declination	−50° 49′ 25″
Apparent magnitude (V)
Characteristics
Spectral type	K1V / D?
U−B color index	0.45
B−V color index	0.812^[1]
V−R color index	0.45
R−I color index	0.40
Astrometry

Proper motion (μ)	RA: 2092.86 ± 0.27^[1] mas/yr Dec.: 653.21 ± 0.30^[1] mas/yr
Parallax (π)	92.74 ± 0.32^[1] mas
Distance	35.2 ± 0.1 ly (10.78 ± 0.04 pc)

Details

Mass	0.79 M_☉
Radius	0.855 ± 0.005 R_☉
Luminosity (bolometric)	0.47^{[note 1]} L_☉
Temperature	5188 K
Metallicity	[Fe/H] = -0.24
Rotation	31 days
Age	2.4 × 10⁹^[3] years

Other designations
13 G. Eridani, GJ 86, HD 13445, HIP 10138, HR 637, SAO 232658
Database references
SIMBAD	data
Exoplanet Archive	data
ARICNS	data
Extrasolar Planets Encyclopaedia	data

Gliese 86 (13 G. Eridani) is a K-type main-sequence star approximately 35 light-years away in the constellation of Eridanus. It has been confirmed that a white dwarf orbits the primary star. In 1998 the European Southern Observatory announced that an extrasolar planet was orbiting the star.^[4]

Stellar components

The primary companion (Gliese 86 A) is a K-type main-sequence star of spectral type K1V. The characteristics in comparison to our Sun are 79% the mass, 86% the radius, and 50% the luminosity. The star has a close-orbiting massive Jovian planet.

Gliese 86 B is a white dwarf located around 21 AU from the primary star, making the Gliese 86 system one of the tightest binaries known to host an extrasolar planet.^[5] It was discovered in 2001 and initially suspected to be a brown dwarf,^[6] but high contrast observations in 2005 suggested that the object is probably a white dwarf, as its spectrum does not exhibit molecular absorption features which are typical of brown dwarfs.^[7] Assuming the white dwarf has a mass about half that of our Sun and that the linear trend observed in radial velocity measurements is due to Gliese 86 B, a plausible orbit for this star around Gliese 86 A has a semimajor axis of 18.42 AU and an eccentricity of 0.3974.^[8]

Planetary system

The preliminary astrometric measurements made with the Hipparcos space probe suggest the planet has an orbital inclination of 164.0° and a mass 15 times Jupiter, which would make the object a brown dwarf.^[9] However, further analysis suggests the Hipparcos measurements are not precise enough to reliably determine astrometric orbits of substellar companions, thus the orbital inclination and true mass of the candidate planet remain unknown.^[10] It was discovered by the Swiss 1.2 m Leonhard Euler Telescope operated by the Geneva Observatory.^[11]

The radial velocity measurements of Gliese 86 show a linear trend once the motion due to this planet are taken out. This may be associated with the orbital motion of the white dwarf companion.

The Gliese 86 system^[12]
Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	>3.91 ± 0.32 M_J	0.1130 ± 0.0065	15.76491 ± 0.00039	0.0416 ± 0.0072	—	—

Notes

↑ From ${\begin{smallmatrix}L=4\pi R^{2}\sigma T_{{{\rm {eff}}}}^{4}\end{smallmatrix}}$ , where ${\begin{smallmatrix}L\end{smallmatrix}}$ is the luminosity, ${\begin{smallmatrix}R\end{smallmatrix}}$ is the radius, ${\begin{smallmatrix}T_{{{\rm {eff}}}}\end{smallmatrix}}$ is the effective surface temperature and ${\begin{smallmatrix}\sigma \end{smallmatrix}}$ is the Stefan–Boltzmann constant

References

↑ 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. Vizier catalog entry
↑ C. Cincunegui and P. J. D. Mauas (2004). "Library of flux-calibrated echelle spectra of southern late-type dwarfs with different activity levels". Astronomy and Astrophysics 414 (2): 699–706. Bibcode:2004A&A...414..699C. doi:10.1051/0004-6361:20031671.
↑ Mamajek, Eric E.; Hillenbrand, Lynne A. (November 2008). "Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics". The Astrophysical Journal 687 (2): 1264–1293. arXiv:0807.1686. Bibcode:2008ApJ...687.1264M. doi:10.1086/591785.
↑ "Extrasolar Planet in Double Star System Discovered from La Silla" (Press release). Garching, Germany: European Southern Observatory. November 24, 1998. Retrieved December 29, 2012.
↑ Raghavan et al.; Henry, Todd J.; Mason, Brian D.; Subasavage, John P.; Jao, Wei‐Chun; Beaulieu, Thom D.; Hambly, Nigel C. (2006). "Two Suns in The Sky: Stellar Multiplicity in Exoplanet Systems". The Astrophysical Journal 646 (1): 523–542. arXiv:astro-ph/0603836. Bibcode:2006ApJ...646..523R. doi:10.1086/504823.
↑ Els, S. G. et al. (2001). "A second substellar companion in the Gliese 86 system. A brown dwarf in an extrasolar planetary system". Astronomy and Astrophysics 370 (1): L1–L4. Bibcode:2001A&A...370L...1E. doi:10.1051/0004-6361:20010298.
↑ Mugrauer, M. and Neuhäuser, R. (2005). "Gl86B: a white dwarf orbits an exoplanet host star". Monthly Notices of the Royal Astronomical Society: Letters 361 (1): L15–L19. arXiv:astro-ph/0506311. Bibcode:2005MNRAS.361L..15M. doi:10.1111/j.1745-3933.2005.00055.x.
↑ Lagrange, A.-M. et al. (2006). "New constrains on Gliese 86 B. VLT near infrared coronographic imaging survey of planetary hosts". Astronomy and Astrophysics 459 (3): 955–963. Bibcode:2006A&A...459..955L. doi:10.1051/0004-6361:20054710.
↑ Han et al.; Black, David C.; Gatewood, George (2001). "Preliminary astrometric masses for proposed extrasolar planetary companions". The Astrophysical Journal Letters 548 (1): L57–L60. Bibcode:2001ApJ...548L..57H. doi:10.1086/318927.
↑ Pourbaix, D. and Arenou, F. (2001). "Screening the Hipparcos-based astrometric orbits of sub-stellar objects". Astronomy and Astrophysics 372 (3): 935–944. arXiv:astro-ph/0104412. Bibcode:2001A&A...372..935P. doi:10.1051/0004-6361:20010597.
↑ http://obswww.unige.ch/~udry/planet/coralie.html
↑ Butler, R. P. et al. (2006). "Catalog of Nearby Exoplanets". The Astrophysical Journal 646 (1): 505–522. arXiv:astro-ph/0607493. Bibcode:2006ApJ...646..505B. doi:10.1086/504701.

External links

"Gliese 86". Extrasolar Visions. Retrieved 2008-08-02.
"Gliese 86 / HR 637 AB". SolStation. Retrieved 2008-08-02.

Coordinates: 02^h 10^m 14^s, −50° 50′ 00″

← Star systems within 35–40 light-years →

Star systems (including brown dwarf systems) within 35–40 light-years from Earth.

Giant star

K III	Arcturus (36.7 ± 0.3 ly; 1 star)

A
(White)

IV	Delta Capricorni «Scheddi» (38.6 ± 0.4 ly; 2 stars)

V	Denebola (36.2 ± 0.4 ly; 1 star)

F V (Yellow-white)	Beta Virginis «Zavijava» (35.6 ± 0.3 ly; 2 stars) Gamma Serpentis (36.3 ± 0.3 ly; 1 star) Theta Persei (36.6 ± 0.3 ly; 2 stars) Zeta Doradus (38.0 ± 0.2 ly; 2 stars) Iota Pegasi (38.3 ± 0.3 ly; 2 stars) Gamma Virginis «Porrima» (38.7 ± 0.4 ly; 2 stars) Zeta Trianguli Australis (39.5 ± 0.3 ly; 2 stars)

G
(Yellow)

IV	Eta Boötis «Muphrid» (37.0 ± 0.3 ly; 2 stars)

V	Delta Trianguli (35.4 ± 0.3 ly; 2 stars) 11 Leonis Minoris (36.5 ± 0.3 ly; 2 stars) Lambda Serpentis (38.3 ± 0.4 ly; 1 star) Zeta Reticuli (39.4 ± 0.3 ly; 2 stars) 85 Pegasi (39.5 ± 0.4 ly; 3 stars)

K V
(Orange)

Wolf 635 (35.1 ± 0.4 ly; 2 stars)
HR 9038 (35.2 ± 0.2 ly; 2 stars)
Gliese 86 (35.6 ± 0.2 ly; 2 stars, 1 planet: b)
HR 6806 (36.2 ± 0.2 ly; 1 star)
54 Piscium (36.2 ± 0.3 ly; 1 star, 1 brown dwarf, 1 planet: b)
HD 74576 (36.3 ± 0.2 ly; 1 star)
HD 85512 (36.4 ± 0.3 ly; 1 star, 1 planet: b)
HD 115404 (36.6 ± 0.4 ly; 2 stars)
ADS 48 (36.7 ± 0.6 ly; 3 stars: A
B
Gliese 2)
Gliese 208 (37.1 ± 0.6 ly; 1 star)
Gliese 902 (37.2 ± 0.3 ly; 1 star)
Gliese 169 (37.4 ± 0.5 ly; 1 star)
HR 5553 (37.6 ± 0.4 ly; 2 stars)
Gliese 773.6 (38.5 ± 5.8 ly; 1 star)
HD 125072 (38.6 ± 0.4 ly; 1 star)
Gliese 414 (38.9 ± 0.5 ly; 2 stars)
Gliese 798 (39.5 ± 0.6 ly; 1 star)
HR 3384 (39.7 ± 0.3 ly; 1 star)
V538 Aurigae (39.9 ± 0.4 ly; 1 star)

M V (Red dwarf)	Gliese 488 (35.2 ± 0.4 ly; 1 star) HIP 57050 (36.2 ± 1.1 ly; 1 star, 1 planet: b)

Brown
dwarf

WISE 2313-0837 (~35.9 ly; 1 brown dwarf)
WISE 0325+0831 (~36.5 ly; 1 brown dwarf)
WISE 0038+2768 (~36.9 ly; 1 brown dwarf)
WISE 0627-1114 (~37.2 ly; 1 brown dwarf)
WISE 1959-3338 (~37.2 ly; 1 brown dwarf)
WISE 0623-0456 (~37.5 ly; 1 brown dwarf)
WISE 2325-4105 (~37.5 ly; 1 brown dwarf)
WISE 2340-0745 (~37.8 ly; 1 brown dwarf)
WISE 0759-4904 (~38.8 ly; 1 brown dwarf)
WISE 0751-7634 (~39.1 ly; 1 brown dwarf)
WISE 1653+4444 (~39.5 ly; 1 brown dwarf)

In left column are stellar classes of primary members of star systems. Bold are systems containing at least one component with absolute magnitude of +8.5 or brighter. Italic are systems without known trigonometric parallax.

v t e Stars of Eridanus

Bayer	α (Achernar) β (Cursa) γ (Zaurak) δ (Rana) ε ζ (Zibal) η (Azha) θ (Acamar) ι κ λ μ ν ξ ο¹ (Beid) ο² (40, Keid) π ρ¹ ρ² ρ³ τ¹ τ² (Angetenar) τ³ τ⁴ τ⁵ τ⁶ τ⁷ τ⁸ τ⁹ υ¹ (Theemin) υ² (Beemin) υ³ υ⁴ φ χ ψ ω

Flamsteed	4 5 6 7 14 15 17 20 21 22 24 25 29 30 32 35 37 39 45 46 47 51 53 (Sceptrum) 54 55 56 58 59 60 62 63 64 66 68

Variable	R RT RX RZ SV TZ UX UY XZ YY AH AQ AS BV BW CC CP CW DL DO DU DZ EF EI EK EL EM EP EX GU GW GY GZ KT

HR	486 487 506 520 573 701 789 807 814 826 827 853 859 862 875 892 895 912 913 929 935 953 955 957 968 983 997 1016 1024 1049 1050 1060 1062 1075 1076 1091 1098 1106 1108 1116 1117 1120 1125 1139 1143 1157 1182 1186 1187 1189 1190 1195 1206 1214 1219 1232 1235 1246 1249 1258 1263 1265 1267 1272 1274 1275 1293 1299 1332 1353 1359 1366 1367 1374 1384 1386 1410 1421 1431 1438 1439 1447 1450 1452 1461 1462 1476 1483 1487 1488 1495 1513 1521 1536 1545 1579 1595 1614 1625 1671

HD	11965 12894 13808 18742 19210 19850 20356 22379 24098 24834 26584 26625 27660 28185 29163 30562 30856

Gliese	Gliese 86 GJ 1062

Other	82 G. DEN 0255-4700 GD 50 HIP 12961 L 369-44 LHS 1723 LP 771-095 2MASS J04151954-0935066 2MASS J04390101-2353083 WASP-22 WASP-50 WASP-78 WASP-79

Former	WX (V1241 Tauri)

List

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