CN emission was detected in comet C/2019 Q4 (Borisov) with Q_CN production = 4 x 10E24 molecules/s with the 4.2-m William Herschel Telescope (+ ISIS spectrograph) on 2019-Sep-20.2 UT (Ref. A. Fitzsimmons et al. Sep 2019 Electronic Telegram No. 4670)

— Charles Bell (@cbellh47) September 23, 2019