S Crucis



S Crucis is a star in the constellation Crux. A Cepheid variable, its apparent magnitude ranges from 6.22 to 6.92 over $-6.1$. It is a yellow-white supergiant that pulsates between spectral types F6Ib-II and G1Ib-II.

S Crucis is a pulsating variable star of the δ Cephei type, a Classical Cepheid variable. Its mean radius is and that radius varies by up to  during its 4.7-day pulsation cycle. Over the same cycle, the effective temperature varies between $-21.1$ and $5.9$. The star is thought to be 116 million years old; it has exhausted its core hydrogen and left the main sequence.