BY Draconis
70 Ophiuchi is a variable star with a magnitude range for the two stars combined of 4.00 to 4.03. The type of variability is uncertain and it is not clear which of the two components causes the variations. It has been suspected of being either a BY Draconis variable or an RS Canum Venaticorum variable, and a period of 1.92396 days has been measured.