What is the surface temperature of RR Lyrae stars?

RR Lyrae stars typically have surface temperatures ranging from about 4,500 to 7,500 Kelvin. These temperatures can vary depending on the specific evolutionary stage and pulsation properties of the star. Generally, cooler RR Lyrae stars exhibit a redder color, while the hotter ones appear bluer. Their classification as variable stars is often associated with these temperature variations during their pulsation cycle.