Compare the brightness of Rho Cas in the image above
with its brightness in the image below. In the upper image of 6 Oct.
1999 Rho Cas
is brighter than V373 Cas, the star to Rho Cas'
upper left. V373 Cas is of 5.9th visual magnitude, with
regular photometric brightness
changes of less than 0.1 magnitude. In the upper image Rho Cas'
visual brightness is about 4.5 mag., which decreased to 5.3 mag.
in the image
below (more comparable to V373 Cas) during the 2000 outburst of the yellow hypergiant.
The lower image was observed on 17 Nov. 2001, about a year after the
eruption of 2000. Rho Cas brightend up to ~4.4 mag.,
becoming visibly brighter than V373 Cas in this low resolution image.
Rho Cas becomes also brighter than Sigma Cas which is of 4.88 visual