Visual observations of variable stars make up the largest component of the AAVSO International Database now containing over 10 million observations on approximately 4,000 variable stars. These stars are primarily large-amplitude (visual range greater than one magnitude). The types of variables include; pulsating (Mira, semiregular, RV Tauri, Cepheids), eruptive or cataclysmic (dwarf nova, nova, recurrent nova, novalike, supernova, symbiotic), R Coronae Borealis, nebular (T Tauri, flare), irregular, and suspected variables. The observations on these stars are sent directly to AAVSO Headquarters. We also have several hundred eclipsing binary and RR Lyrae stars in the visual observing program and their observaitons are sent directly to the chairmen of these special committees.

Due to the wide range of periods and magnitudes of variation from type to type, some stars need more frequent observations and require more specific reporting of their observing time than others. Below is a table that gives the suggested frequency of observations together with the digit of the Julian day their observations should be reported at to the AAVSO.

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