€After Polars were identified, Charles et
al (1979)
found an
X-ray emitting V~13 star, AO Psc, with an optical spectrum like that of Polars, but without
any identifiable polarisation
€They also showed variability on three different timescales
now known to be
–the orbital,
–the spin period
of the white dwarf &
–the mixture of
the two (beat/synodic period)