Deep images of the Centaurus and Coma clusters reveal two spectacular arcs of diffuse light that stretch for over 100 kpc , yet are just a few kpc wide .
At a surface brightness of m _ { b } \sim 27 - 28 th arcsec ^ { -2 } , the Centaurus arc is the most striking example known of structure in the diffuse light component of a rich galaxy cluster .
We use numerical simulations to show that the Centaurus feature can be reproduced by the tidal debris of a spiral galaxy that has been tidally disrupted by the gravitational potential of NGC 4709 .
The surface brightness and narrow dimensions of the diffuse light suggest that the disk was co-rotating with its orbital path past pericenter .
Features this prominent in clusters will be relatively rare , although at fainter surface brightness levels the diffuse light will reveal a wealth of structure .
Deeper imaging surveys may be able to trace this feature for several times its presently observed extent and somewhere along the tidal debris , a fraction of the original stellar component of the disk will remain bound , but transformed into a faint spheroidal galaxy .
It should be possible to confirm the galactic origin of the Centaurus arc by observing planetary nebulae along its length with redshifts close to that of NGC 4709 .