AAVSO Headquarters, 25 Birch Street, Cambridge, MA 02138
at the 94th Spring Meeting of the AAVSO, March 25, 2005, received November 28,
2005, revised January 19, 2006, accepted January 20, 2006
Abstract The d Scuti stars are pulsating
variables useful for studies of stellar structure and evolution. Though new and
improved models of stars and stellar physics have increased our understanding
of these variables in recent years, some aspects of their behavior such as period
changes are still poorly understood. Period changes may arise from a
variety of evolutionary and non-evolutionary causes including undiscovered
binarity, nonlinear mode-coupling, and secular changes in chemical structure.
In this review, I will briefly summarize current observations and theories on
period changes in d Scuti stars, and suggest ways that the AAVSO
community can contribute to this important field.