CI Cyg

Special Notice #219: Eclipse of the symbiotic star CI Cygni

October 12, 2010: As noted by U. Munari et al (ATel #2913, 2010 October 9), the symbiotic star CI Cygni is currently undergoing an eclipse of the outbursting star.  CI Cyg has declined from about magnitude 9.7 in late August 2010 to V=11.1 currently.

Special Notice #215: Brightening of the symbiotic star CI Cyg

August 24, 2010: Observer Gary Poyner (Birmingham, UK) reports that the symbiotic star CI Cygni has noticeably brightened over the past few days.  Poyner reports the star at a magnitude of m(vis)=9.8 on 2010 August 23.92 (JD 2455432.42). CI Cyg has been in a slow rise for several months, beginning immediately after the end of the last outburst.  Continued monitoring of CI Cyg over the next several weeks and months will be useful for better understanding the nature of this star system and its outbursts.

CI Cygni

CI Cygni's Days of Discovery

The Henry Draper (HD) Catalogue, named for the first photographer of stellar spectra, is a nine volume publication (released from 1918 through 1924) that contains the positions, th