GJ 526

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GJ 526
Observation data
Epoch J2000      Equinox J2000
Constellation Boötes
Right ascension 13h 45m 43.77665s[1]
Declination +14° 53′ 29.4635″[1]
Apparent magnitude (V) 8.464[2]
Characteristics
Spectral type M1.5 V[3]
U−B color index +1.04[4]
B−V color index +1.48[4]
Variable type Flare[5]
Astrometry
Radial velocity (Rv) +15.3[6] km/s
Proper motion (μ) RA: +1778.45[1] mas/yr
Dec.: –1456.44[1] mas/yr
Parallax (π) 184.00 ± 1.07[7] mas
Distance 17.7 ± 0.1 ly
(5.43 ± 0.03 pc)
Details
Mass 0.28[5] M
Radius 0.582±0.021[2] R
Luminosity 0.011[8] L
Surface gravity (log g) 4.80[3] cgs
Temperature 3,474±50[2] K
Metallicity [Fe/H] –0.086[2] dex
Rotation 52.3±1.7 d[9]
Rotational velocity (v sin i) 1.00[2] km/s
Other designations
LAL 25372, BD+15°2620, CD+15°2620, HD 119850, HIP 67155, PLX 3135, SAO 100695, TYC 899-789-1, Wolf 498.[10]
Database references
SIMBAD data

GJ 526 (Lalande 25372, Wolf 498) is a red dwarf star in the northern constellation of Boötes. It has an apparent visual magnitude of 8.5,[2] which is too faint to be seen with the naked eye. Based upon an annual parallax shift of 0.184 arc seconds as measured by the Hipparcos satellite, this system is 17.7 light-years (5.43 parsecs) from Earth.[7]

History of observations[edit]

This star is known at least from 1801, when it was included to Lalande's stellar catalogue Histoire Céleste Française.[11] In 1847 edition of Lalande's catalogue by Francis Baily it was assigned number 25372, since it sometimes designated as Lalande 25372 or LAL 25372.[12]

High proper motion of this star and its large parallax were known at least from 1911, when Frank Schlesinger published a paper where he announced its parallax 152±mas and mentioned its proper motion value of 2.3 arcsec.[13] In 1919, German astronomer Max Wolf included GJ 526 in his catalogue of high proper motion stars, giving it the identifier 498.[14]

Properties[edit]

GJ 526 is a flare star, which means it undergoes sporadic increases in brightness of up to 1–6 magnitudes.[5] It is a main sequence red dwarf with a stellar classification of M1.5 V.[3] GJ 526 is smaller than the Sun, with 28%[5] of the mass and 58.2%[2] of the radius. It shines with just 1.1% of the luminosity of the Sun,[8] with its stellar atmosphere radiating at an effective temperature of 3,474 K.[2]

GJ 526 has been examined for an excess of radiation in the infrared. The presence of an infrared excess can be taken as an indication of a debris disk orbiting the star. However, no such excess was discovered around GJ 526.[8]

References[edit]

  1. ^ a b c d van Leeuwen, F. (November 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. 
  2. ^ a b c d e f g h Houdebine, E. R. (September 2011), "Observation and modelling of main-sequence star chromospheres - XVI. Rotation of dK5 stars", Monthly Notices of the Royal Astronomical Society 407 (3): 1657–1673, Bibcode:2011MNRAS.416.2233H, doi:10.1111/j.1365-2966.2011.19199.x. 
  3. ^ a b c Frasca, A.; et al. (December 2009), "REM near-IR and optical photometric monitoring of pre-main sequence stars in Orion. Rotation periods and starspot parameters", Astronomy and Astrophysics 508 (3): 1313–1330, Bibcode:2009A&A...508.1313F, doi:10.1051/0004-6361/200913327. 
  4. ^ a b Cowley, A. P.; Hiltner, W. A.; Witt, A. N. (December 1967), "Spectral classification and photometry of high proper motion stars", Astronomical Journal 72: 1334–1340, Bibcode:1967AJ.....72.1334C, doi:10.1086/110413. 
  5. ^ a b c d Gershberg, R. E.; et al. (November 1999), "Catalogue and bibliography of the UV Cet-type flare stars and related objects in the solar vicinity", Astronomy and Astrophysics Supplement 139: 555–558, Bibcode:1999A&AS..139..555G, doi:10.1051/aas:1999407. 
  6. ^ Evans, D. S. (June 20–24, 1966), "The Revision of the General Catalogue of Radial Velocities", in Batten, Alan Henry; Heard, John Frederick, Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30, University of Toronto: International Astronomical Union, Bibcode:1967IAUS...30...57E. 
  7. ^ a b Gatewood, George (2008). "Astrometric Studies of Aldebaran, Arcturus, Vega, the Hyades, and Other Regions". The Astronomical Journal 136 (1): 452–460. Bibcode:2008AJ....136..452G. doi:10.1088/0004-6256/136/1/452. 
  8. ^ a b c Avenhaus, H.; et al. (December 2012), "The nearby population of M-dwarfs with WISE: a search for warm circumstellar dust", Astronomy & Astrophysics 548: A105, arXiv:1209.0678, Bibcode:2012A&A...548A.105A, doi:10.1051/0004-6361/201219783. 
  9. ^ Suárez Mascareño, A.; et al. (September 2015), "Rotation periods of late-type dwarf stars from time series high-resolution spectroscopy of chromospheric indicators", Monthly Notices of the Royal Astronomical Society 452 (3): 2745−2756, arXiv:1506.08039, Bibcode:2015MNRAS.452.2745S, doi:10.1093/mnras/stv1441. 
  10. ^ "HD 119850 -- Flare Star", SIMBAD Astronomical Database (Centre de Données astronomiques de Strasbourg), retrieved 2014-01-11. 
  11. ^ Lalande, Joseph Jérôme Le Français de (1801). "Histoire Céleste Française". Paris, Imprimerie de la République. Google Books id: f9AMAAAAYAAJ. Page with GJ 526: 74
  12. ^ Baily, Francis; Lalande, Joseph Jérôme Le Français de (1847). "Catalogue of those stars in the Histoire Celeste Francaise of Jerome Delalande, for which tables of reduction to the epoch 1800 habe been published by Prof. Schumacher". London (1847). Bibcode:1847cshc.book.....B. Google Books id: oc0-AAAAcAAJ. Page with GJ 526: 635.
  13. ^ Schlesinger, F. (1911). "Photographic determinations of stellar parallax made with the Yerkes refractor. V.". The Astrophysical Journal 33: 353–374. Bibcode:1911ApJ....33..353S. doi:10.1086/141859. 
  14. ^ Wolf, M. (1919), "Katalog von 1053 staerker bewegten Fixsternen", Veroeffentlichungen der Badischen Sternwarte zu Heidelberg (in German) 7 (10): 195–219, Bibcode:1919VeHei...7..195W. 

Notes[edit]