Long-period variable star

[1] The term was first used in the 19th century, before more precise classifications of variable stars, to refer to a group that were known to vary on timescales typically hundreds of days.

[10] The AAVSO LPV Section covers "Miras, Semiregulars, RV Tau and all your favorite red giants".

Recent researches have increasingly focused on the long period variables as only AGB and possibly red giant tip stars.

Most LPVs, including all Mira variables, are thermally-pulsing asymptotic giant branch stars with luminosities several thousand times the sun.

Binary interactions, dust formation, rotation, or non-radial oscillations have all been proposed as causes, but all have problems explaining the observations.