Variable Stars
A variable star is a star where its brightness as seen from Earth fluctuates. The study of variable stars involves the recording of its magnitude, and how that fluctuates over time. The plotting of a variable star's magnitude vs. time is known as a light curve. The light curve plotting of variable stars combined with the study of supernovae events help physicists understand the formation of the universe.
Variable Star Types
Variable stars have a wide number of classifications, with the main types listed below.
Intrinsic
Pulsating Stars
Cepheids
Type I Classical
Type II W Virginis
RR Lyrae
RV Tauri
Long-Period Variables (LPVs)
Mira Type
Semiregular
Eruptive (cataclysmic stars)
Extrinsic
Eclipsing Binaries
Rotating Variables
Variable Star Resources
American Association of Variable Star Observers - (AAVSO) is a non-profit worldwide scientific and educational organization of amateur and professional astronomers who are interested in stars that change in brightness—variable stars.
arXiv.org Astrophysics - An e-print service in the fields of physics, mathematics, computer science, quantitative biology, quantitative finance and statistics maintained Cornell University.
Astrophysics Data System - The ADS maintains three bibliographic databases containing more than 10.8 million records: Astronomy and Astrophysics, Physics, and arXiv e-prints.
The British Astronomical Association: Variable Star Section - The VSS was formed in 1890, the year the BAA was founded, with the aim of collecting and analysing observations of variable stars.
Konkoly Observatory, Hungary - Variable Stars - The Information Bulletin on Variable Stars is a bulletin of the Commissions 27 and 42 of the International Astronomical Union, published by the Konkoly Observatory, Budapest, Hungary.
Royal Astronomical Society of New Zealand - The RASNZ has links to Variable Stars South, a group focused on Variable Stars in the Southern skies.
The SIMBAD astronomical database provides basic data, cross-identifications, bibliography and measurements for astronomical objects outside the solar system.