  The results of a photometric survey of the Fornax dwarf spheroidal galaxy are
presented herein. Accurate photometry in two colours (V and I) was collected
over a 10 square degree area centred on the Fornax system with the aim of
searching for extra-tidal structure. The data were complete to a magnitude of
V=20, or approximately one magnitude brighter than the Fornax red clump stars.
Stars were selected with a colour and magnitude lying near the Fornax red giant
branch, thereby reducing contamination from the field star population. We were
thus able to probe the outer structure of this dwarf galaxy. Immediately
visible was a shell-like structure located 1.3 degrees NW from the centre of
Fornax, approximately 30 arcmin beyond the nominal tidal radius at this
position angle. We have measured the absolute visual magnitude of this feature
to be M_V ~ -7. The feature is aligned with a previously reported shell (age
approximately 2 Gyr) located near the core radius of Fornax. A statistical
analysis of the extra-tidal stellar distribution further revealed two lobes
situated on the Fornax minor axis which are aligned with the two shell-like
features. The two-lobed structure combined with the two shells provide strong
evidence that Fornax has experienced a merger event in the relatively recent
past.
