Zeta1 Scorpii

For other stars with this Bayer designation, see Zeta Scorpii. Zeta1 Scorpii (Zeta1 Sco, ζ1 Scorpii, ζ1 Sco) is a B-type hypergiant star in the constellation of Scorpius.[8] It has an apparent visual magnitude which varies between 4.66 and 4.86.[3] It is a member of the Scorpius OB1 association,[9] and the open star cluster NGC 6231, also known as the "northern jewel box" cluster. Around 36 times as massive as the Sun, it is also one of the most luminous stars known in the Galaxy, with an estimated bolometric luminosity of around 850,000 times that of the Sun and a radius 103 times that of the Sun.[4]

The stellar wind from this supergiant is expelling matter from the star at the rate of 1.55 × 10−6 solar masses per year, or roughly the equivalent to the Sun's mass every 640,000 years.[4]

ζ1 Scorpii forms a naked eye double with ζ2 Scorpii, but the stars are merely coincidentally near in the line of sight from Earth. ζ2 is a mere 155 light years distant and much less luminous in real terms. ζ1 Scorpii can also be distinguished from ζ2, due to the latter's orange hue especially in long-exposure photographs.

References[edit]
Categories:
 * 1) ^ Jump up to:a b c d e  Note: see VizieR catalogue I/311.
 * 2) ^ Jump up to:a b c
 * 3) ^ Jump up to:a b c zet 1 Sco, database entry, The combined table of GCVS Vols I-III and NL 67-78 with improved coordinates, General Catalogue of Variable Stars, Sternberg Astronomical Institute, Moscow, Russia. Accessed on line November 20, 2009. (Quick look: Zet+1+Sco)
 * 4) ^ Jump up to:a b c d e f g h i
 * 5) Jump up^
 * 6) Jump up^
 * 7) Jump up^
 * 8) ^ Jump up to:a b HIP 82671 -- Emission-line Star, database entry, SIMBAD. Accessed on line November 20, 2009.
 * 9) Jump up^ Zeta-1 Sco, Stars, Jim Kaler. Accessed on line November 20, 2009.
 * Scorpius (constellation)
 * B-type hypergiants
 * Hipparcos objects
 * Bayer objects
 * Henry Draper Catalogue objects
 * Emission-line stars