Alert Notice 662: V818 Sco (Sco X-1) multiwavelength campaign
February 20, 2019: Drs. Sara Motta and Jari Kajava (University of Oxford) have requested AAVSO observers' assistance in monitoring the binary X-ray source V818 Sco (Sco X-1) in support of a large multiwavelength observing campaign being carried out from now through 2019 February 24.