  From VLT/NACO diffraction-limited images of RY~Sgr, we report the first
direct detection of heterogeneities in the circumstellar envelope of a R
Coronae Borealis variable star. Several bright and very large dust clouds are
seen in various directions at several hundred stellar radii from RY Sgr,
revealing high activity for the ejection of stellar material by R CrB
variables. These observations do support the current interpretation that
optically thick dust clouds are formed around the surface of this type of
variable stars and, when passing between the star and the observer, produce the
huge and sudden declines characterizing these objects in visible light. This is
the first direct confirmation of a scenario proposed about 70 years ago.
