Mu Crucis, Latinized from μ Crucis, is the seventh-brightest star in the constellation Crux commonly known as the Southern Cross. μ Crucis is a wide double star of spectral class B stars, magnitude 4.0 and 5.2 respectively. They lie about 370 light-years away, and both stars are likely physically attached. The brighter component is known as μ1 Crucis or μ Crucis A, while the fainter is μ2 Crucis or μ Crucis B.
μ1 Crucis is the brighter of the two stars with an apparent magnitude of 4.0. It is a hot massive main sequence or subgiant star, over a thousand times as luminous as the sun.
μ2 Crucis is the fainter of the pair. Its apparent magnitude is 5.2 and it is a Be star, a star spinning so quickly that it has ejected a disc of material that creates emission lines in its spectrum. The disc is inclined at 36° to our line of sight.[11]
References
^ abcdefghPerryman, M. A. C.; et al. (April 1997). "The HIPPARCOS Catalogue". Astronomy & Astrophysics. 323: L49 –L52. Bibcode:1997A&A...323L..49P.
^ abcdefJohnson, H. L.; Iriarte, B.; Mitchell, R. I.; Wisniewskj, W. Z. (1966). "UBVRIJKL photometry of the bright stars". Communications of the Lunar and Planetary Laboratory. 4 (99): 99. Bibcode:1966CoLPL...4...99J.
^ abEvans, 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. University of Toronto: International Astronomical Union. Bibcode:1967IAUS...30...57E.
^ abKilian, J. (1994). "Chemical abundances in early B-type stars. V. Metal abundances and LTE/NLTE comparison". Astronomy and Astrophysics. 282: 867. Bibcode:1994A&A...282..867K.
