KY Cygni
KY Cygni is ’n rooisuperreus van spektraaltipe M3.5Ia in die sterrebeeld Swaan. Dit is een van die grootste sterre bekend, met ’n geraamde radius van 1 420 R☉ (sonradiusse). Dit is ook een van die helderstes: sowat 300 000 of meer keer so helder as die Son. Dit is sowat 5 000 ligjare van die Aarde af.
| KY Cygni | ||||
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| KY Cygni se grootte in vergelyking met dié van Betelgeuse. | ||||
| Sterrebeeld | Swaan | |||
| Spektraaltipe | M3-4I[1] (M3,5Ia[2]) | |||
| Waarnemingsdata (Epog J2000) | ||||
| Regte klimming | 20h 25m 58.05s[3] | |||
| Deklinasie | +38° 21′ 07.6″[3] | |||
| Skynmagnitude (m) | 11,14[4] (10,60 – 11,74)[5] | |||
| Absolute magnitude (M) | -8,18[1] | |||
| B-V-kleurindeks | 3,39[4] | |||
| U-B-kleurindeks | 2,91[4] | |||
| Besonderhede | ||||
| Radius (R☉) | 1 420 (2 850?)[1] | |||
| Ligsterkte (L☉) | 138 000[4] - 270 000[1] | |||
| Temperatuur (K) | 3 500[1] | |||
| Afstand (ligjaar) | ~5 000 | |||
| Eienskappe | ||||
| Veranderlikheid | Stadig, onreëlmatig[2] | |||
| Ander name | ||||
| KY Cyg, GSC 03152-01140, IRAS 20241+3811, IRC+40415, TYC 3152-1140-1, RAFGL 2575, UCAC2 45230193, 2MASS J20255805+3821076 | ||||
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Waarnemings
wysigKY Cyg lê naby die helder oop sterreswerm NGC 6913, maar behoort waarskynlik nie daartoe nie. Sy ligging is naby dié van die helder ster γ Cygni.[6] Dit is in 1930 as ’n veranderlike ster geïdentifiseer[7] en hernoem tot KY Cygni (sien Benaming van veranderlike sterre).[8] Die spektraaltipe is vasgestel op M3Ia, met klein aanpassings sedertdien.[9]
Die ster is baie rooi omdat dit sowat 7,75 magnitudes teen sigbare golflengtes verloor.[1]
Eienskappe
wysigKY Cygni is ’n groot, helder superreus met ’n sterk sterwind. Dit verloor massa teen ’n enorme tempo, hoër as die meeste ander rooisuperreuse, en word soms beskryf as ’n koel hiperreus.[4][10] Sy eienskappe is onseker, maar sy temperatuur is sowat 3 500 K en sy ligsterkte meer as 100 000 L☉.[1][4]
KY Cygni is ’n veranderlike ster, maar met geen duidelike periodisiteit nie. Soms wissel dit vinnig, en ander kere is dit vir lang tye taamlik konstant.[6]
Sien ook
wysigVerwysings
wysig- ↑ 1,0 1,1 1,2 1,3 1,4 1,5 1,6 Levesque, Emily M.; Massey, Philip; Olsen, K. A. G.; Plez, Bertrand; Josselin, Eric; Maeder, Andre; Meynet, Georges (2005). "The Effective Temperature Scale of Galactic Red Supergiants: Cool, but Not As Cool As We Thought". The Astrophysical Journal. 628 (2): 973. arXiv:astro-ph/0504337. Bibcode:2005ApJ...628..973L. doi:10.1086/430901.
- ↑ 2,0 2,1 KY Cyg, database entry, The combined table of GCVS Vols I-III and NL 67-78 with improved coordinates, General Catalogue of Variable Stars Geargiveer 20 Junie 2017 op Wayback Machine, Sternberg Astronomical Institute, Moscow, Russia. URL besoek op 12 November 2010
- ↑ 3,0 3,1 Cutri, R. M.; Skrutskie, M. F.; Van Dyk, S.; Beichman, C. A.; Carpenter, J. M.; Chester, T.; Cambresy, L.; Evans, T.; Fowler, J.; Gizis, J.; Howard, E.; Huchra, J.; Jarrett, T.; Kopan, E. L.; Kirkpatrick, J. D.; Light, R. M.; Marsh, K. A.; McCallon, H.; Schneider, S.; Stiening, R.; Sykes, M.; Weinberg, M.; Wheaton, W. A.; Wheelock, S.; Zacarias, N. (2003). "VizieR Online Data Catalog: 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)". VizieR On-line Data Catalog: II/246. Originally published in: University of Massachusetts and Infrared Processing and Analysis Center. 2246: 0. Bibcode:2003yCat.2246....0C.
- ↑ 4,0 4,1 4,2 4,3 4,4 4,5 Mauron, N.; Josselin, E. (2011). "The mass-loss rates of red supergiants and the de Jager prescription". Astronomy and Astrophysics. 526: A156. arXiv:1010.5369. Bibcode:2011A&A...526A.156M. doi:10.1051/0004-6361/201013993.
- ↑ Alfonso-Garzón, J.; Domingo, A.; Mas-Hesse, J. M.; Giménez, A. (2012). "The first INTEGRAL-OMC catalogue of optically variable sources". Astronomy & Astrophysics. 1210: arXiv:1210.0821. arXiv:1210.0821. Bibcode:2012arXiv1210.0821A. doi:10.1051/0004-6361/201220095.
{{cite journal}}: Onbekende parameter|class=geïgnoreer (hulp) - ↑ 6,0 6,1 Romano, G. (1969). "Researches with the Schmidt telescopes. III. Variable stars in the field of gamma Cygni". Memorie della Società Astronomia Italiana. 40: 375. Bibcode:1969MmSAI..40..375R.
- ↑ Hoffmeister, Cuno (1930). "Relative Koordinaten, Oerter und Karten neuer Veraenderlicher". Mitteilungen der Sternwarte zu Sonneberg. 17: 1. Bibcode:1930MiSon..17....1H.
- ↑ Ahnert, P.; Van Schewick, H.; Hoffmeister, C. (1941). "Die Veraenderlichen Sterne der noerdlichen Milchstrasse. Teil II". Kleine Veroeffentlichungen der Universitaetssternwarte zu Berlin Babelsberg. 6: 4.1. Bibcode:1941KVeBB...6....4A.
- ↑ White, N. M.; Wing, R. F. (1978). "Photoelectric two-dimensional spectral classification of M supergiants". Astrophysical Journal. 222: 209. Bibcode:1978ApJ...222..209W. doi:10.1086/156136.
- ↑ Stickland, D. J. (1985). "IRAS observations of the cool galactic hypergiants". The Observatory. 105: 229. Bibcode:1985Obs...105..229S.
Eksterne skakels
wysig- KY Cygni by jumk.de/astronomie
- KY Cygni by astronomy.com
Hierdie artikel is vertaal uit die Engelse Wikipedia
