  We investigate the role of thermal instability, arising from radiative
cooling of an optically thin, dusty plasma, by linear stability analysis. The
corresponding isobaric stability condition for condensation mode is found to be
modified significantly by the degree of ionization and concentration of finite
sized, relatively heavy, and negatively charged dust particles. It has been
shown that though the fundamental wave mode is similar in nature to the one in
absence of dust particles, a new dust-wave mode can propagate in such a plasma.
It is conjectured that the presence of negatively charged dust particles may
considerably affect the stability of various astrophysical structures against
thermal instability, which can not be explained with the help of gravitational
instability.
