An irregular variable star, similar to R Coronae Borealis, its brightness varies between 4.1mag and 6.2mag in a cycle that lasts slightly less than one year. Suitable comparison stars are σ (4.9mag) and τ Cas (4.87mag). This exceptionally luminous supergiant is located 3400 light-years away. In the sky, we see it near the star β Cas.