T Cen is a bright southern RV Tauri variable, ranging from m(vis) of 5.5 to 9th magnitude. Successive minima are separated by just under 100 days, but since the minima alternate, the true period is about 190 days. The RV Tauri stars are highly evolved giant stars that vary due to pulsation. They're similar in behavior and structure to other evolved pulsators like the W Virginis stars (or "Type II Cepheids") although their evolutionary state is somewhat ambiguous. While their pulsations are believed to be radial in nature, there's some other actor at work, and the light curves are believed to exhibit chaos at some level. T Cen appears to show slow variations in its depth of minima over time. Many RV Taus are almost regular from cycle-to-cycle, while others (like R Scuti) appear to be random in nature to the point where they appear to briefly stop pulsating.
Prepared By: Matthew Templeton