Massive stars that form the Gould Belt OB associations are known to have higher multiplicity than solar-type stars. Due to their luminosity and close vicinity, they are optimal targets for speckle interferometry. Among the members of the Cas–Tau OB association, observed with the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (BTA SAO RAS), a binary system, HI P10944 (B9VpSi, G=5m. 53), was discovered for the first time. We present the results of speckle interferometry monitoring of the star from 2007 to 2025, covering almost the entire orbital period (P₎ₑ₁=20. 90 yrs). Based on the measured positional parameters, an orbit was constructed and the sum of the masses of the system’s components was determined (M*=4. 26 0. 06M_).
Butorina et al. (Mon,) studied this question.