TITLE: GCN CIRCULAR NUMBER: 21610 SUBJECT: LIGO/VIRGO G298048: SALT optical spectra of the candidate optical/NIR counterpart of the gravitational wave G298048 in NGC4993. DATE: 17/08/20 06:14:37 GMT FROM: Stephen Potter at SAAO M. Shara (AMNH), T. Williams (SAAO), P. Vaisanen (SAAO/SALT), S. Potter (SAAO), E. Romero Colmenero (SAAO/SALT), S. Crawford (SAAO), D. Buckley (SAAO), J Cooke (Swinburne), Igor Andreoni (Swinburne), Tyler Pritchard (Swinburne), Jirong Mao (YNAO) Spectra of an unresolved source at coordinates RA=197.4504, DEC=-23.3815 near the galaxy NGC 4993, obtained with the Robert Stobie Spectrograph on the Southern African Large Telescope at UT 17:07:19.703 on 18 August 2017 and at UT 16:58:32.764 on 19 August 2017 during early twilight. The spectra extends between 3600-8000 Angstroms with a resolution of ~300. The spectra is heavily blended with the host galaxy. After subtraction of the host galaxy spectra from the 18 August, the source shows a spectra increasing in flux from 8000 A to 5000 A, which then decreases in flux after 4500 A. The spectra from the 19 August 2017 was taken early twilight and too noisy to say anything definitive.