Zeta2 is located near the blue-white supergiant starζ1 Scorpii in Earth's sky. In astronomical terms, ζ2 is much closer to the Sun and unrelated to ζ1 except for line-of sight co-incidence. ζ1 is about 6,000 light-years away and probably an outlying member ofopen star clusterNGC 6231 (also known as the "northern jewel box" cluster). ζ2 can also be distinguished from its optical partner, ζ1, because of its orangish colour especially in long-exposureastrophotographs.
^Setiawan, J.; Pasquini, L.; Da Silva, L.; Hatzes, A. P.; von Der Lühe, O.; Girardi, L.; De Medeiros, J. R.; Guenther, E. (2004). "Precise radial velocity measurements of G and K giants. Multiple systems and variability trend along the Red Giant Branch".Astronomy and Astrophysics.421: 241.Bibcode:2004A&A...421..241S.doi:10.1051/0004-6361:20041042-1.
^abLandi Dessy, J.; Keenan, P. C. (November 1966), "Spectral Types on the MK System for Forty-Three Bright Southern Stars, K2-M6",Astrophysical Journal,146: 587,Bibcode:1966ApJ...146..587L,doi:10.1086/148925.
^abcHR 6271, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr.,CDS IDV/50. Accessed on line November 20, 2009.
^Evans, D. S. (June 20–24, 1966), Batten, Alan Henry; Heard, John Frederick (eds.), "The Revision of the General Catalogue of Radial Velocities",Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30, vol. 30, University of Toronto:International Astronomical Union, p. 57,Bibcode:1967IAUS...30...57E.
^"The Colour of Stars",Australia Telescope, Outreach and Education, Commonwealth Scientific and Industrial Research Organisation, December 21, 2004, archived fromthe original on 2013-12-03, retrieved2012-01-16.
