Gliese 65

Coordinates: Sky map 01h 39m 01.54s, −17° 57′ 01.8″
Source: Wikipedia, the free encyclopedia.
Gliese 65 A/B
Gliese 65 is located in the constellation Cetus.
Gliese 65 is located in the constellation Cetus.
     Gliese 65
Location of Gliese 65 in the constellation Cetus

Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cetus
Gliese 65 A (BL Ceti)
Right ascension 01h 39m 01.3773s[1]
Declination –17° 57′ 02.587″[1]
Apparent magnitude (V) 12.8[2]
Gliese 65 B (UV Ceti)
Right ascension 01h 39m 01.6377s[3]
Declination –17° 57′ 01.001″[3]
Apparent magnitude (V) 12.8[2]
Characteristics
Gliese 65 A (BL Ceti)
Spectral type M5.5V[4]
U−B color index 1.10
B−V color index 1.87
Variable type
UV Cet[5]
Gliese 65 B (UV Ceti)
Spectral type M6 V[4]
Variable type
UV Cet[6]
Distance
8.770 ± 0.010 ly
(2.689 ± 0.003 pc)
Gliese 65 A (BL Ceti)
mas/yr
Absolute magnitude (MV)15.7[2]
Argument of periastron
(ω)
(secondary)		103.2±0.1°
Details
Gliese 65 A
Rotational velocity (v sin i)
30.6±2[8] km/s
LHS
 10
Database references
SIMBADThe system
A (BL Cet)
B (UV Cet)

Gliese 65, also known as Luyten 726-8, is a

variable star designations
BL Ceti and UV Ceti.

Star system

UV Ceti by Andrew Posa (1982)

The star system was discovered in 1948 by

Gm). The Gliese 65 system is approximately 2.63 parsecs (8.58 ly) from Earth's Solar System, in the constellation Cetus, and is thus the seventh-closest star system to Earth. Its own nearest neighbor is Tau Ceti
, 0.98 pc (3.20 ly) away from it. If km/s then approximately 28,700 years ago Gliese 65 was at its minimal distance of 2.21 pc (7.2 ly) from the Sun.[12]

Gliese 65 A was later found to be a

UV Ceti variable
type, but it is not nearly as remarkable or extreme in its behavior as its companion star UV Ceti.

An ultraviolet light curve for UV Ceti, adapted from Beskin et al. (2017).[13] The main plot shows the full flare event and the inset plot shows the time around peak brightness with an expanded time scale.

Soon after[

spectral type M6V.[4]

Both stars are listed as spectral standard stars for their respective classes, being considered typical examples of the classes.[4]

In approximately 31,500 years, Gliese 65 will have a close encounter with Epsilon Eridani at the minimal distance of about 0.93 ly. Gliese 65 can penetrate a conjectured Oort cloud about Epsilon Eridani, which may gravitationally perturb some long-period comets. The duration of mutual transit of two star systems within 1 ly from each other is about 4,600 years.[14]

Gliese 65 is a possible member of the Hyades Stream.[15]

Candidate planet

In 2024, a candidate super-Neptune-mass planet was detected in the Gliese 65 system via astrometry with VLTI/GRAVITY. If real, it would orbit one of the two stars (it is unclear which) with a period of 156 days.[7]

The Gliese 65 planetary system[7][nb 1]
Companion
(in order from star) 		Mass Semimajor axis
(AU) 		Orbital period
(days) 		Eccentricity Inclination Radius
(unconfirmed) 39±7 M🜨
36±6 M🜨 		0.283±0.002
0.274±0.002 		156±1 0.33±0.30
0.27±0.21 		88±6°
89±9° 		—

References

  1. ^
    S2CID 244398875
    . Gaia DR3 record for this source at VizieR.
  2. ^
    S2CID 159041104
    .
  3. ^
    S2CID 244398875
    . Gaia DR3 record for this source at VizieR.
  4. ^
    doi:10.1086/191611
    .
  5. ^
    Centre de Données astronomiques de Strasbourg
    . Retrieved 2009-12-16.
  6. ^
    Centre de Données astronomiques de Strasbourg
    . Retrieved 2009-12-16.
  7. ^
    arXiv:2404.08746
    .
  8. ^ a b c d e f g h i Kervella, Pierre; et al. (October 2016), "The red dwarf pair GJ65 AB: inflated, spinning twins of Proxima. Fundamental parameters from PIONIER, NACO, and UVES observations", Astronomy & Astrophysics, 593,
    doi:10.1051/0004-6361/201628631
  9. ^ a b c d MacDonald, James; et al. (June 2018), "The Magnetic Binary GJ 65: A Test of Magnetic Diffusivity Effects", The Astrophysical Journal, 860 (1): 15,
    doi:10.3847/1538-4357/aac2c0
  10. ^ a b Barnes, J. R.; et al. (October 2017), "Surprisingly different star-spot distributions on the near equal-mass equal-rotation-rate stars in the M dwarf binary GJ 65 AB", Monthly Notices of the Royal Astronomical Society, 471 (1): 811–823,
    doi:10.1093/mnras/stx1482
  11. doi:10.1086/106322
    .
  12. Centre de Données astronomiques de Strasbourg
    . Retrieved 2010-04-14.
  13. S2CID 125084280
    .
  14. arXiv:1004.1557 [astro-ph.SR
    ].
  15. S2CID 55727428. Archived from the original
    on 2012-07-09. Retrieved 2010-04-18.

Notes

  1. ^ The parameters are slightly different depending on whether the planet orbits star A (above) or star B (below).

Further reading

External links
Retrieved from "https://en.wikipedia.org/w/index.php?title=Gliese_65&oldid=1219286661"