  Luminous Blue Variables (LBVs) are massive stars that are likely to be a
transitionary phase between O stars and hydrogen-free classical Wolf-Rayet
stars. The variability of these stars has been an area of study for both
professional and amateur astronomers for more than a century. In this paper, we
present five years of precision photometry of the classical LBV P Cygni taken
with the BRITE-Constellation nanosatellites. We have analyzed these data with
Fourier analysis to search for periodicities that could elucidate the drivers
of variability for these stars. These data show some long-timescale variability
over the course of all six calendar years of observations, but the frequencies
needed to reproduce the individual light curves are not consistent from one
year to the next. These results likely show that there is no periodic
phenomenon present for P Cygni, meaning that the variability is largely
stochastic. We interpret the data as being caused by internal gravity waves
similar to those seen in other massive stars, with P Cygni exhibiting a larger
amplitude and lower characteristic frequency than the main-sequence or blue
supergiant stars previously studied. These results show evidence that LBVs may
be an extrapolation of the blue supergiants, which have previously been shown
to be an extension of main-sequence stars in the context of the stochastic
low-frequency photometric variability.
