Alpha Ophiuchi

Alpha Ophiuchi
Die ligging van α Ophiuchi in die Slangdraer (in die rooi sirkel).
Sterrebeeld	Slangdraer
Spektraaltipe	A5 III[1] / K5–7 V[2]
Soort	Dubbelster
Waarnemingsdata (Epog J2000)
Regte klimming	17h 34m 56.06945s[3]
Deklinasie	+12° 33′ 36.1346″[3]
Skynmagnitude (m)	2,07[4]
Absolute magnitude (M)	1,248[5]
B-V-kleurindeks	+0,15[4]
U-B-kleurindeks	+0,10[4]
Wentelperiode	3 148,4 dae
Besonderhede
Komponent 1	α Oph A
Massa (M☉)	2,40+0,23−0,37[2]
Radius (R☉)	2,6[6]
Ligsterkte (L☉)	25,1–25,6[7]
Temperatuur (K)	7 880–8 050[7]
Rotasiespoed (km/s)	240[7]
Komponent 2	α Oph B
Massa (M☉)	0,85+0,06−0,04[2]
Eienskappe
Ouderdom (jaar)	0,77±0,03 miljard[8]
Ander name
Ras Alhague, Rasalhague, 55 Ophiuchi, BD+12° 3252, FK5 656, HD 159561, HIP 86032, HR 6556, SAO 102932[9]
Portaal    Sterrekunde

Alpha Ophiuchi (α Ophiuchi, afgekort as Alpha Oph of α Oph), ook bekend as Rasalhague,^[10] is ’n dubbelster en die helderste ster in die sterrebeeld Slangdraer (Ophiuchus).

1. ↑ Verwysingfout: Invalid <ref> tag; no text was provided for refs named aj74_375
2. ↑ ^{2,0 2,1 2,2} Verwysingfout: Invalid <ref> tag; no text was provided for refs named apj726_2_104
3. ↑ ^{3,0 3,1} Verwysingfout: Invalid <ref> tag; no text was provided for refs named aaa474_2_653
4. ↑ ^{4,0 4,1 4,2} Verwysingfout: Invalid <ref> tag; no text was provided for refs named clpl4
5. ↑ Gatewood, George (2005). "An Astrometric Study of the Binary Star α Ophiuchi". The Astronomical Journal. 130 (2): 809–814. Bibcode:2005AJ....130..809G. doi:10.1086/431723. ISSN 0004-6256.
6. ↑ Verwysingfout: Invalid <ref> tag; no text was provided for refs named aass85_3_1015
7. ↑ ^{7,0 7,1 7,2} Verwysingfout: Invalid <ref> tag; no text was provided for refs named apj742_1_9
8. ↑ Verwysingfout: Invalid <ref> tag; no text was provided for refs named apj701_1_209
9. ↑ Verwysingfout: Invalid <ref> tag; no text was provided for refs named SIMBAD
10. ↑ "IAU Catalog of Star Names" (in Engels). Geargiveer vanaf die oorspronklike op 29 Mei 2020. Besoek op 28 Julie 2016.