Sadalmelik

Alpha Aquarii
	Sadalmelik se ligging (in die rooi sirkel).
Sterrebeeld	Waterdraer
Bayer-naam	Alpha Aquarii
Spektraaltipe	G2 Ib
Soort	Superreus
	Waarnemingsdata (Epog J2000)
Regte klimming	22h 05m 47.03593s
Deklinasie	−00° 19′ 11.4568″
Skynmagnitude (m)	2,94
B-V-kleurindeks	+0,97
U-B-kleurindeks	+0,699
	Besonderhede
Massa (M☉)	6,5
Radius (R☉)	77
Ligsterkte (L☉)	3 000
Ouderdom (jaar)	53 miljoen
Temperatuur (K)	5 210
	Ander name
	El Melik, Rucbah, Saad el Melik, Sadalmelek, Sadalmelik, Sadlamulk, α Aqr, Alpha Aquarii, Alpha Aqr, 34 Aquarii, 34 Aqr, BD−01 4246, FK5 827, HD 209750, HIP 109074, HR 8414, SAO 145862.
Portaal	Sterrekunde

Sadalmelik (ook genoem Alpha Aquarii of α Aqr) is volgens data van die Hipparcos-sending sowat 520 ligjare van die Son af geleë.^[2] Dit is die tweede helderste ster in die sterrebeeld Waterdraer (Aquarius) en het ’n skynbare magnitude van 2,94.^[3]

Eienskappe

Die ster is 53 miljoen jaar oud^[1] en het ontwikkel in ’n superreus met ’n sterreklassifikasie van G2 Ib.^[1] Sy massa is 6,5 keer dié van die Son,^[1] sy radius sowat 77 keer^[8] en sy ligsterkte 3 000 keer die Son s’n.^[9] Sy oppervlaktemperatuur is sowat 5 210 K.^[1] Dit is wat Sadalmelik die geel skynsel van ’n G-tipe ster gee.^[10] Waarnemings deur die Chandra-X-straalsterrewag toon dit straal min X-strale uit in vergelyking met G-tipe hoofreekssterre. Dit is ’n algemene kenmerk van vroeë G-tipe reusesterre.^[9]

Sadalmelik het ’n visuele metgesel, 2MASS J22055176-0017468, met ’n skynbare magnitude van sowat 12,2. Dit lê teen ’n hoekskeiding van 110,4 boogsekondes van Sadalmelik, teen ’n posisiehoek van 40°.^[6]

Naam

Die ster se Bayer-naam is "Alpha Aquarii". Die tradisionele naam, "Sadalmelik", kom van die Arabiese uitdrukking سعد الملك sa‘d al-malik, "geluk van die koning". Die oorsprong van die naam is onbekend.

In 2016 het die Internasionale Astronomiese Unie se sternaamwerkgroep (WGSN) die naam "Sadalmelik" vir die ster goedgekeur.^[11]

Verwysings

↑ ^1,0 ^1,1 ^1,2 ^1,3 ^1,4 ^1,5 ^1,6 ^1,7 Lyubimkov, Leonid S. et al. (February 2010), "Accurate fundamental parameters for A-, F- and G-type Supergiants in the solar neighbourhood", Monthly Notices of the Royal Astronomical Society 402 (2): 1369–1379, doi:10.1111/j.1365-2966.2009.15979.x, Bibcode: 2010MNRAS.402.1369L
↑ ^2,0 ^2,1 ^2,2 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode: 2007A&A...474..653V
↑ ^3,0 ^3,1 ^3,2 ^3,3 Cousins, A. W. J. (1984), "Standardization of Broadband Photometry of Equatorial Standards", South African Astronomical Observatory Circulars 8: 59, Bibcode: 1984SAAOC...8...59C
↑ HR 8414, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line October 3, 2008.
↑ Sadalmelik – ster in dubbelstelsel, databasisinskrywing, Simbad. Besoek op 3 Oktober 2008.
↑ ^6,0 ^6,1 Inskrywing 22058-0019, The Washington Double Star Catalog, United States Naval Observatory. Besoek op 18 November 2008.
↑ pp. 51, 148, Star-names and Their Meanings, Richard Hinckley Allen, New York: G. E. Stechert, 1899.
↑ Nordgren, Tyler E. et al. (December 1999), "Stellar Angular Diameters of Late-Type Giants and Supergiants Measured with the Navy Prototype Optical Interferometer", The Astronomical Journal 118 (6): 3032–3038, doi:10.1086/301114, Bibcode: 1999AJ....118.3032N
↑ ^9,0 ^9,1 Ayres, Thomas R.; Brown, Alexander; Harper, Graham M. (July 2005), "Chandra Observations of Coronal Emission from the Early G Supergiants α and β Aquarii", The Astrophysical Journal 627 (1): L53–L56, doi:10.1086/431977, Bibcode: 2005ApJ...627L..53A
↑ "The Colour of Stars", Australia Telescope, Outreach and Education (Commonwealth Scientific and Industrial Research Organisation), December 21, 2004, archived from the original on 2012-03-10, https://www.webcitation.org/6630AbtJZ?url=http://outreach.atnf.csiro.au/education/senior/astrophysics/photometry_colour.html, besoek op 2012-01-16
↑ "Bulletin of the IAU Working Group on Star Names, No. 1" (PDF). Besoek op 28 Julie 2016.

Eksterne skakels

Alpha Aquarii Aladin image viewer
Sadalmelik op WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Artikels en foto's
Hierdie artikel is vertaal uit die Engelse Wikipedia

[mnras402_2_1369-1] 1,0 ^1,1 ^1,2 ^1,3 ^1,4 ^1,5 ^1,6 ^1,7 Lyubimkov, Leonid S. et al. (February 2010), "Accurate fundamental parameters for A-, F- and G-type Supergiants in the solar neighbourhood", Monthly Notices of the Royal Astronomical Society 402 (2): 1369–1379, doi:10.1111/j.1365-2966.2009.15979.x, Bibcode: 2010MNRAS.402.1369L

[aaa474_2_653-2] 2,0 ^2,1 ^2,2 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode: 2007A&A...474..653V

[saoc8_59-3] 3,0 ^3,1 ^3,2 ^3,3 Cousins, A. W. J. (1984), "Standardization of Broadband Photometry of Equatorial Standards", South African Astronomical Observatory Circulars 8: 59, Bibcode: 1984SAAOC...8...59C

[bsc1-4] HR 8414, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line October 3, 2008.

[sb0-5] Sadalmelik – ster in dubbelstelsel, databasisinskrywing, Simbad. Besoek op 3 Oktober 2008.

[wds-6] 6,0 ^6,1 Inskrywing 22058-0019, The Washington Double Star Catalog, United States Naval Observatory. Besoek op 18 November 2008.

[allen-7] . 51, 148, Star-names and Their Meanings, Richard Hinckley Allen, New York: G. E. Stechert, 1899.

[aj118_6_3032-8] Nordgren, Tyler E. et al. (December 1999), "Stellar Angular Diameters of Late-Type Giants and Supergiants Measured with the Navy Prototype Optical Interferometer", The Astronomical Journal 118 (6): 3032–3038, doi:10.1086/301114, Bibcode: 1999AJ....118.3032N

[apj627_1_L53-9] 9,0 ^9,1 Ayres, Thomas R.; Brown, Alexander; Harper, Graham M. (July 2005), "Chandra Observations of Coronal Emission from the Early G Supergiants α and β Aquarii", The Astrophysical Journal 627 (1): L53–L56, doi:10.1086/431977, Bibcode: 2005ApJ...627L..53A

[csiro-10] "The Colour of Stars", Australia Telescope, Outreach and Education (Commonwealth Scientific and Industrial Research Organisation), December 21, 2004, archived from the original on 2012-03-10, https://www.webcitation.org/6630AbtJZ?url=http://outreach.atnf.csiro.au/education/senior/astrophysics/photometry_colour.html, besoek op 2012-01-16

[WGSN1-11] "Bulletin of the IAU Working Group on Star Names, No. 1" (PDF). Besoek op 28 Julie 2016.

[2]

[3]

[1]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]