SX Phoenicis star

An SX Phoenicis star is a pulsating subdwarf star, smaller than the Sun, with a spectral type A2 to F5, typically found in globular clusters. The period of pulsation is in the range 0.04 to 0.8 day with an amplitude of about 0.7 magnitude. SX Phe stars are close cousins of Delta Scuti stars.