Alfa Kentauri

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Alfa Kentauri AB[note 1]

Alfa Kentauri AB je najsvetlija zveza vidljiva s leve strane, koja formira trozvezdani sistem sa Proksima Kentauri, zaokruženom crveno. Najsvetliji zvezdani sistem sa desne strane je Beta Kentauri.
Opservacioni podaci
Epoha J2000.0      Ravnodnevnica J2000.0
Sazvežđe Kentauri
Alfa Kentauri A
Rektascenzija 14h 39m 36.49400s[1]
Deklinacija −60° 50′ 02.3737″[1]
Prividna magnituda (V) +0.01[2]
Alfa Kentauri B
Rektascenzija 14h 39m 35.06311s[1]
Deklinacija −60° 50′ 15.0992″[1]
Prividna magnituda (V) +1.33[2]
Karakteristike
A
Spektralni tip G2V[3]
U−B indeks boja +0.24[2]
B−V indeks boja +0.71[2]
B
Spektralni tip K1V[3]
U−B indeks boja +0.68[2]
B−V indeks boja +0.88[2]
Astrometrija
A
Radijalna brzina (Rv)−21,4±0,76[4] km/s
Sopstveno kretanje (μ) RA: −3679.25[1] mas/g
Dek.: 473.67[1] mas/g
Paralaksa (π)754.81 ± 4.11[1] mas
Rastojanje4.37[5] sg
Apsolutna magnituda (MV)4.38[6]
B
Radijalna brzina (Rv)−18,6±1,64[4] km/s
Sopstveno kretanje (μ) RA: −3614.39[1] mas/g
Dek.: 802.98[1] mas/g
Paralaksa (π)754.81 ± 4.11[1] mas
Rastojanje4.37[5] sg
Apsolutna magnituda (MV)5.71[6]
Detalji
Alfa Kentauri A
Masa1.100[7] M
Poluprečnik1,2234±0,0053[8] R
Luminoznost1.519[7] L
Površinska gravitacija (log g)4.30[9] cgs
Temperatura5,790[7] K
Metaličnost [Fe/H]0.20[7] dex
Rotacija22±5,9 d[10]
Rotaciona brzina (v sin i)2,7±0,7[10] km/s
Alfa Kentauri B
Masa0.907[7] M
Poluprečnik0,8632±0,0037[8] R
Luminoznost0.5002[7] L
Površinska gravitacija (log g)4.37[9] cgs
Temperatura5,260[7] K
Metaličnost0.23[7]
Rotacija36[11] days
Rotaciona brzina (v sin i)1,1±0,8[12] km/s
Starost5,3±0,3[13] Gyr
Orbita[14]
PrimarnaA
KompanjonB
Period (P)79,91±0,011 g
Velika poluosa (a)17,57±0,022
Ekscentricitet (e)0,5179±0,00076
Inklinacija (i)79,205±0,041°
Longituda uzlaznog čvora (Ω)204,85±0,084°
Apsidna epoha (T)1875,66±0,012
Argument perihela (ω)
(sekundarni)
231,65±0,076°
Druge oznake
Gliese 559, FK5 538, CD−60°5483, CCDM J14396-6050, GC 19728
α Cen A: Rigil Kentaurus, Rigil Kent, α1 Centauri, HR 5459, HD 128620, GCTP 3309.00, LHS 50, SAO 252838, HIP 71683
α Cen B: Toliman, α2 Centauri, HR 5460, HD 128621, LHS 51, HIP 71681
Referentne baze podataka
SIMBADAB
A
B
Ekstrasolarna arhivadata
ARICNSdata
Enciklopedija
ekstrasolarnih planeta
data
Alfa Kentauri

Alfa Kentauri ili α Cen ili Toliman je najsjajnija zvezda u sazvežđu Kentaur (Centaurus), koje je vidljivo od januara do jula, a kulminira tokom aprila i nije vidljivo sa severne polulopte na geografskim širinama većim od 30°. Alfa Kentaur je Zemlji najbliža zvezda, posle Sunca.

Iako je najbliža zvezda Zemlji (posle Sunca) tek je peta po sjaju sa svojom prividnom magnitudom 0,06, a nalazi se na 4,3 svetlosne godine od Zemlje. Koordinate Alfa Kentaura u sfernom nebeskom ekvatorskom koordinatnom sistemu su 14 sati i 36 minuta (rektascenzija) i -60°38' (deklinacija). Ova zvezda pripada spektralnoj klasi G2 (prema Harvardskoj spektralnoj klasifikaciji), kao i Sunce.

Alfa Kentauri je trojni sistem, čiji član je i Proksima Kentauri, najbliža zvezda Suncu.

Procene rastojanja[uredi | uredi izvor]

Alfa Kentauri AB procene rastojanja
Izvor Paralaksa (mas) Rastojanje (pc) Rastojanje (ly) Rastojanje (Pm) Reference
Henderson (1839) 1160±110 0,86+0,09
−0,07
2.57 ± 0.53 26,6+2,8
−2,3
[15]
Henderson (1842) 912,8±64 1.03 ± 0.15 3.34 ± 0.5 33,8+2,5
−2,2
[16]
Maklir (1851) 918,7±34 1,09±0,04 3,55+0,14
−0,13
32.4 ± 2.5 [17]
Moesta (1868) 880±68 1,14+0,10
−0,08
3,71+0,31
−0,27
35,1+2,9
−2,5
[18]
Gil & Elkin (1885) 750±10 1,333±0,018 4,35±0,06 41,1+0,6
−0,5
[19]
Roberts (1895) 710±50 1.32 ± 0.2 4.29 ± 0.65 43,5+3,3
−2,9
[20]
Vuli et al. (1970) 743±7 1,346±0,013 4,39±0,04 41,5±0,4 [21]
Glis & Jahreib (1991) 749,0±4,7 1,335±0,008 4,355±0,027 41,20±0,26 [22]
van Altena et al. (1995) 749,9±5,4 1,334±0,010 4,349+0,032
−0,031
41,15+0,30
−0,29
[23]
Periman et al. (1997) (A and B) 742,12±1,40 1,3475±0,0025 4,395±0,008 41,58±0,08 [24]

[25] [26] [27]

Sederhjelm (1999) 747,1±1,2 1,3385+0,0022
−0,0021
4,366±0,007 41,30±0,07 [28]
van Liuven (2007) (A) 754,81±4,11 1,325±0,007 4,321+0,024
−0,023
40,88±0,22 [29]
van Liuven (2007) (B) 796,92±25,90 1,25±0,04 4,09+0,14
−0,13
37.5 ± 2.5 [30]
RECONS TOP100 (2012) 747,23±1,17[note 2] 1,3383±0,0021 4,365±0,007 41,29±0,06 [31]

Napomene[uredi | uredi izvor]

  1. ^ Proxima Centauri is gravitationally bound to the α Centauri system, but for practical and historical reasons it is described in detail in its own article.
  2. ^ Weighted parallax based on parallaxes from van Altena et al. (1995) and Söderhjelm (1999).

Reference[uredi | uredi izvor]

  1. ^ a b v g d đ e ž z i Van Leeuwen, F. (2007). „Validation of the new Hipparcos reduction”. Astronomy and Astrophysics. 474 (2): 653—664. Bibcode:2007A&A...474..653V. arXiv:0708.1752Slobodan pristup. doi:10.1051/0004-6361:20078357. 
  2. ^ a b v g d đ Ducati, J. R. (2002). „VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system”. CDS/ADC Collection of Electronic Catalogues. 2237: 0. Bibcode:2002yCat.2237....0D. 
  3. ^ a b Torres, C. A. O.; Quast, G. R.; da Silva, L .; de la Reza, R.; Melo, C. H. F.; Sterzik, M. (2006). „Search for associations containing young stars (SACY)”. Astronomy and Astrophysics. 460 (3): 695—708. Bibcode:2006A&A...460..695T. ISSN 0004-6361. arXiv:astro-ph/0609258Slobodan pristup. doi:10.1051/0004-6361:20065602. 
  4. ^ a b Valenti, Jeff A.; Fischer, Debra A. (2005). „Spectroscopic Properties of Cool Stars (SPOCS). I. 1040 F, G, and K Dwarfs from Keck, Lick, and AAT Planet Search Programs”. The Astrophysical Journal Supplement Series. 159 (1): 141—166. Bibcode:2005ApJS..159..141V. ISSN 0067-0049. doi:10.1086/430500Slobodan pristup. 
  5. ^ a b Wilkinson, John (2012). „The Sun and Stars”. New Eyes on the SunSlobodan pristup ograničen dužinom probne verzije, inače neophodna pretplata. Astronomers' Universe. str. 219–236. ISBN 978-3-642-22838-4. ISSN 1614-659X. doi:10.1007/978-3-642-22839-1_10. 
  6. ^ a b P. A. Wiegert; M. J. Holman (1997). „The stability of planets in the Alpha Centauri system”. The Astronomical Journal. 113: 1445 — 1450. Bibcode:1997AJ....113.1445W. arXiv:astro-ph/9609106Slobodan pristup. doi:10.1086/118360. 
  7. ^ a b v g d đ e ž Thévenin, F.; Provost, J.; Morel, P.; Berthomieu, G.; Bouchy, F.; Carrier, F. (2002). „Asteroseismology and calibration of alpha Cen binary system”. Astronomy & Astrophysics. 392: L9. Bibcode:2002A&A...392L...9T. arXiv:astro-ph/0206283Slobodan pristup. doi:10.1051/0004-6361:20021074. 
  8. ^ a b Kervella, P.; Bigot, L.; Gallenne, A.; Thévenin, F. (januar 2017). „The radii and limb darkenings of α Centauri A and B. Interferometric measurements with VLTI/PIONIER”. Astronomy & Astrophysics. 597. A137. Bibcode:2017A&A...597A.137K. arXiv:1610.06185Slobodan pristup. doi:10.1051/0004-6361/201629505. 
  9. ^ a b Gilli G.; Israelian G.; Ecuvillon A.; Santos N. C.; Mayor M. (2006). „Abundances of Refractory Elements in the Atmospheres of Stars with Extrasolar Planets”. Astronomy and Astrophysics. 449 (2): 723—36. Bibcode:2006A&A...449..723G. arXiv:astro-ph/0512219Slobodan pristup. doi:10.1051/0004-6361:20053850. libcode 2005astro.ph.12219G. 
  10. ^ a b Bazot, M.; et al. (2007). „Asteroseismology of α Centauri A. Evidence of rotational splitting”. Astronomy and Astrophysics. 470 (1): 295—302. Bibcode:2007A&A...470..295B. arXiv:0706.1682Slobodan pristup. doi:10.1051/0004-6361:20065694. 
  11. ^ DeWarf, L.; Datin, K.; Guinan, E. (2010). „X-ray, FUV, and UV Observations of α Centauri B: Determination of Long-term Magnetic Activity Cycle and Rotation Period”. The Astrophysical Journal. 722 (1): 343—357. Bibcode:2010ApJ...722..343D. arXiv:1009.1652Slobodan pristup. doi:10.1088/0004-637X/722/1/343. 
  12. ^ Raassen, A. J. J.; Ness, J.-U.; Mewe, R.; Van Der Meer, R. L. J.; Burwitz, V.; Kaastra, J. S. (2003). „Chandra-LETGS X-ray observation of α Centauri: A nearby (G2V + K1V) binary system”. Astronomy & Astrophysics. 400 (2): 671—678. Bibcode:2003A&A...400..671R. doi:10.1051/0004-6361:20021899Slobodan pristup. 
  13. ^ Joyce, M.; Chaboyer, B. (2018). „Classically and Asteroseismically Constrained 1D Stellar Evolution Models of α Centauri a and B Using Empirical Mixing Length Calibrations”. The Astrophysical Journal. 864 (1): 99. Bibcode:2018ApJ...864...99J. arXiv:1806.07567Slobodan pristup. doi:10.3847/1538-4357/aad464. 
  14. ^ Pourbaix, D.; et al. (2002). „Constraining the difference in convective blueshift between the components of alpha Centauri with precise radial velocities”. Astronomy and Astrophysics. 386 (1): 280—285. Bibcode:2002A&A...386..280P. arXiv:astro-ph/0202400Slobodan pristup. doi:10.1051/0004-6361:20020287. 
  15. ^ Henderson, H. (1839). „On the parallax of α Centauri” (PDF). Monthly Notices of the Royal Astronomical Society. 4 (19): 168—169. Bibcode:1839MNRAS...4..168H. doi:10.1093/mnras/4.19.168. 
  16. ^ Henderson, T. (1842). „The Parallax of α Centauri, deduced from Mr. Maclear's Observations at the Cape of Good Hope, in the Years 1839 and 1840”. Memoirs of the Royal Astronomical Society. 12: 370—371. Bibcode:1842MmRAS..12..329H. 
  17. ^ Maclear, T. (1851). „Determination of the Parallax of α 1 and α2 Centauri, from Observations made at the Royal Observatory, Cape of Good Hope, in the Years 1842-3-4 and 1848”. Memoirs of the Royal Astronomical Society. 20: 98. Bibcode:1851MmRAS..20...70M. 
  18. ^ Moesta, C. G. (1868). „Bestimmung der Parallaxe von α und β Centauri” [Determining the parallax of α and β Centauri]. Astronomische Nachrichten (na jeziku: German). 71 (8): 117—118. Bibcode:1868AN.....71..113M. doi:10.1002/asna.18680710802. 
  19. ^ Gill, David; Elkin, W.L. (1885). „Heliometer-Determinations of Stellar Parallax in the Southern Hemisphere”. Memoirs of the Royal Astronomical Society. 48: 188. Bibcode:1885MmRAS..48....1G. 
  20. ^ Roberts, Alex W. (1895). „Parallax of α Centauri from Meridian Observations 1879–1881”. Astronomische Nachrichten. 139 (12): 189—190. Bibcode:1895AN....139..177R. doi:10.1002/asna.18961391202. 
  21. ^ Woolley, R.; Epps, E. A.; Penston, M. J.; Pocock, S. B. (1970). „Woolley 559”. Catalogue of Stars within 25 Parsecs of the Sun. 5: ill. Bibcode:1970ROAn....5.....W. Arhivirano iz originala 08. 10. 2017. g. Pristupljeno 9. 5. 2014. 
  22. ^ Gliese, W.; Jahreiß, H. (1991). „Gl 559”. Preliminary Version of the Third Catalogue of Nearby Stars. Astronomische Rechen-Institut. Pristupljeno 9. 5. 2014. 
  23. ^ Van Altena, W. F.; Lee, J. T.; Hoffleit, E. D. (1995). „GCTP 3309”. The General Catalogue of Trigonometric Stellar Parallaxes (Fourth izd.). Yale University Observatory. Pristupljeno 9. 5. 2014. 
  24. ^ Perryman; et al. (1997). „HIP 71683”. The Hipparcos and Tycho Catalogues. Pristupljeno 9. 5. 2014. 
  25. ^ Perryman; et al. (1997). „HIP 71683”. The Hipparcos and Tycho Catalogues. Pristupljeno 9. 5. 2014. 
  26. ^ Perryman; et al. (1997). „HIP 71681”. The Hipparcos and Tycho Catalogues. Pristupljeno 9. 5. 2014. 
  27. ^ Perryman; et al. (1997). „HIP 71681”. The Hipparcos and Tycho Catalogues. Pristupljeno 9. 5. 2014. 
  28. ^ Söderhjelm, Staffan (1999). „HIP 71683”. Visual binary orbits and masses post Hipparcos. Pristupljeno 9. 5. 2014. 
  29. ^ van Leeuwen, Floor (2007). „HIP 71683”. Validation of the new Hipparcos reduction. 
  30. ^ van Leeuwen, Floor (2007). „HIP 71681”. Validation of the new Hipparcos reduction. 
  31. ^ „The One Hundred Nearest Star Systems”. Research Consortium On Nearby Stars. Georgia State University. 7. 9. 2007. Arhivirano iz originala 12. 11. 2007. g. Pristupljeno 2. 12. 2014. 

Spoljašnje veze[uredi | uredi izvor]

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