The stellar wind from this supergiant is expelling matter from the star at the rate of 1.55 × 10−6solar 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 135 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.
ζ1 Scorpii is a candidate luminous blue variable (cLBV), a star with the luminosity and spectral appearance of an LBV, but one that has not yet shown the characteristic types of variability.[5] It has been classified as dormant or ex-S Doradus variable, an older name for LBVs.[12]
^ abcKozok, J. R. (September 1985), "Photometric observations of emission B-stars in the southern Milky Way", Astronomy and Astrophysics Supplement Series, 61: 387–405, Bibcode:1985A&AS...61..387K
^Evans, D. S. (June 20–24, 1966), "The Revision of the General Catalogue of Radial Velocities", in Batten, Alan Henry; Heard, John Frederick (eds.), 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
^Bernacca, P. L.; Perinotto, M. (1970), "A catalogue of stellar rotational velocities", Contributi Osservatorio Astronomico di Padova in Asiago, 239 (1): 1, Bibcode:1970CoAsi.239....1B