Astronomy:L 1159-16

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Short description: Nearby flare star in the constellation Aries

Coordinates: Sky map 02h 00m 12.959s, +13° 03′ 07.01″

L 1159-16
Observation data
Equinox J2000.0]] (ICRS)
Constellation Aries
Right ascension  02h 00m 12.959s[1]
Declination +13° 03′ 07.01″[1]
Apparent magnitude (V) 12.298[2]
Characteristics
Spectral type M4.5 V[3]
U−B color index +1.37[4]
B−V color index +1.80[4]
R−I color index 1.39[3]
Variable type Flare star
Astrometry
Proper motion (μ) RA: +1092.0[1] mas/yr
Dec.: –1772.9[1] mas/yr
Parallax (π)223.7321 ± 0.0699[5] mas
Distance14.578 ± 0.005 ly
(4.470 ± 0.001 pc)
Absolute magnitude (MV)14.03[6]
Details
Mass0.14[7] M
Radius0.161[8] R
Luminosity0.00135[9] L
Surface gravity (log g)5.05[7] cgs
Temperature3,158[8] K
Metallicity [Fe/H]−0.14[8] dex
Rotational velocity (v sin i)3.8[9] km/s
Age4.8[7] Gyr
Other designations
TZ Ari, 2MASS J02001278+1303112, GCTP 412.02, GJ 83.1, GJ 9066, G 003-033, LFT 171, LHS 11[10]
Database references
SIMBADdata
L 1159-16 is located in the constellation Aries.
L 1159-16 is located in the constellation Aries.
L 1159-16
Location of L 1159-16 in the constellation Aries

L 1159-16 is a red dwarf in the northern constellation of Aries. With a normal apparent visual magnitude of 12.3, it is too faint to be seen by the naked eye, although it lies relatively close to the Sun at a distance of about 14.6 light-years (4.5 parsecs). It is a flare star, which means it can suddenly increase in brightness for short periods of time.

Variability

L 1159-16 is a variable star. It is a flare star, showing brief increases in brightness due to eruptions from its surface. In the ultraviolet, flares of over a magnitude have been observed. In addition it shows longterm variations in brightness which may be due to starspots and rotation, possibly classifying it as a BY Draconis variable.[11] It was given the variable star designation TZ Arietis in 1970.[12]

Planetary system

In June 2019 three candidate planets were reported in orbit around L 1159-16 (GJ 83.1),[13] and two were confirmed in August 2020.[14]

The L 1159-16 (as of 2020)[15] planetary system[14]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
d (unconfirmed) 4.0+1.9
−1.8
M
0.016+0.001
−0.002
1.93177+0.00016
−0.00020
0.09+0.26
−0.09
b[15] 27.9+19
−11
 M
0.403+0.039
−0.047
241.590+4.6
−4.0
0.16+0.32
−0.16
c 70.7+26.3
−21.5
 M
0.871+0.087
−0.100
766.954+16.710−19.237 0.39+0.18
−0.32

In March 2022, astronomers using the Calar Alto Observatory in Spain, as part of the CARMENES survey project, reported they had found no evidence for the planet L 1159-16 b at a period of 241.59 days, and confidently defined candidate L 1159-16 d as nothing more than a spurious chromatic effect of the star, linked to its rotation. They did confirm L 1159-16 c, re-designated it as L 1159-16 b, and updated its parameters.[16]

The L 1159-16 (as of 2022)[17] planetary system[16]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b[17] 0.23±0.02 MJ 0.88±0.02 772.05+2.41
−1.84
0.49+0.06
−0.07

See also

References

  1. 1.0 1.1 1.2 1.3 Zacharias, N. et al. (2003), "The Second U.S. Naval Observatory CCD Astrograph Catalog (UCAC2)", CDS/ADC Collection of Electronic Catalogues 1289, Bibcode2003yCat.1289....0Z. 
  2. Landolt, Arlo U. (July 1992), "UBVRI photometric standard stars in the magnitude range 11.5-16.0 around the celestial equator", Astronomical Journal 104 (1): 340–371, 436–491, doi:10.1086/116242, Bibcode1992AJ....104..340L. 
  3. 3.0 3.1 Riaz, Basmah; Gizis, John E.; Harvin, James (August 2006), "Identification of New M Dwarfs in the Solar Neighborhood", The Astronomical Journal 132 (2): 866–872, doi:10.1086/505632, Bibcode2006AJ....132..866R. 
  4. 4.0 4.1 Nicolet, B. (1978), "Photoelectric photometric Catalogue of homogeneous measurements in the UBV System", Astronomy and Astrophysics Supplement Series 34: 1–49, Bibcode1978A&AS...34....1N. 
  5. Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode2021A&A...649A...1G.  Gaia EDR3 record for this source at VizieR.
  6. Boro Saikia, S. et al. (2018), "Chromospheric activity catalogue of 4454 cool stars. Questioning the active branch of stellar activity cycles", Astronomy and Astrophysics 616: A108, doi:10.1051/0004-6361/201629518, Bibcode2018A&A...616A.108B. 
  7. 7.0 7.1 7.2 Yee, Samuel W.; Petigura, Erik A.; von Braun, Kaspar (2017), "Precision Stellar Characterization of FGKM Stars using an Empirical Spectral Library", The Astrophysical Journal 836 (1): 77, doi:10.3847/1538-4357/836/1/77, Bibcode2017ApJ...836...77Y. 
  8. 8.0 8.1 8.2 Houdebine, Éric R.; Mullan, D. J.; Doyle, J. G.; de la Vieuville, Geoffroy; Butler, C. J.; Paletou, F. (2019), "The Mass–Activity Relationships in M and K Dwarfs. I. Stellar Parameters of Our Sample of M and K Dwarfs", The Astronomical Journal 158 (2): 56, doi:10.3847/1538-3881/ab23fe, Bibcode2019AJ....158...56H. 
  9. 9.0 9.1 McLean, M.; Berger, E.; Reiners, Ansgar (February 2012), "The Radio Activity-Rotation Relation of Ultracool Dwarfs", The Astrophysical Journal 746 (1): 23, doi:10.1088/0004-637X/746/1/23, Bibcode2012ApJ...746...23M. 
  10. "TZ Ari -- Flare Star", SIMBAD Astronomical Database (Centre de Données astronomiques de Strasbourg), http://simbad.u-strasbg.fr/simbad/sim-id?Ident=TZ+Arietis, retrieved 2012-08-18. 
  11. Gershberg, R. E.; Katsova, M. M.; Lovkaya, M. N.; Terebizh, A. V.; Shakhovskaya, N. I. (1999), "Catalogue and bibliography of the UV Cet-type flare stars and related objects in the solar vicinity", Astronomy and Astrophysics Supplement Series 139 (3): 555–558, doi:10.1051/aas:1999407, Bibcode1999A&AS..139..555G. 
  12. Kukarkin, B. V.; Kholopov, P. N.; Perova, N. B. (October 1970), "57th Name-List of Variable Stars", Information Bulletin on Variable Stars 480 (1): 1, Bibcode1970IBVS..480....1K. 
  13. Barnes, J. R. et al. (2019-06-11) (in en), Frequency of planets orbiting M dwarfs in the Solar neighbourhood, Bibcode2019arXiv190604644T. 
  14. 14.0 14.1 Feng, Fabo et al. (2020). Search for Nearby Earth Analogs. III. Detection of ten new planets, three planet candidates, and confirmation of three planets around eleven nearby M dwarfs. doi:10.3847/1538-4365/abb139. 
  15. 15.0 15.1 Planet GJ 9066 b, Extrasolar Planets Encyclopaedia, http://exoplanet.eu/catalog/gj_9066_b/, retrieved 31 March 2022, "Planet Status: Confirmed" 
  16. 16.0 16.1 Quirrenbach, A.; et al. (2022). "The CARMENES search for exoplanets around M dwarfs: Two Saturn-mass planets orbiting active stars". arXiv:2203.16504 [astro-ph.EP].
  17. 17.0 17.1 Planet TZ Ari b, Extrasolar Planets Encyclopaedia, http://exoplanet.eu/catalog/tz_ari_b/, retrieved 31 March 2022, "Planet Status: Confirmed" 

Further reading

External links