2025/12/24 by Mike Goldsmith, Goldsmith, Mike
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #FOS: Physical sciences #Solar and Stellar Astrophysics (astro-ph.SR) #Stellar, planetary, and galactic studies
paper · doi:10.48550/arxiv.2512.21296
openalex publication_date 2025/12/24 · openalex created_date 2025/12/26 · openalex updated_date 2026/07/28
The AAVSO-based historical light curve of the oxygen-rich Mira variable R Leonis is used to determine and analyse the properties of the star's maxima and minima. The pulsation period is found to have shortened by about 3 days over the past two centuries. Superimposed on the mean period are clear modulations on timescales of approximately 35 and 98 years. The depths of extrema show non-random behaviour: minima in particular display strong similarity in depth over extended intervals, with a mean depth difference of 0.26 magnitude for adjacent minima compared to a 0.38 magnitude difference for random pairs. Depth coherence persists for up to about 43 years. Examination of extrema depths over the full observational history of the star reveals gradual long-term changes, consistent with evolution of the circumstellar dust environment.