Discovery of X-shaped Morphology of the Giant Radio Galaxy GRG 0503-286
  The high surface-brightness sensitivity of the GLEAM survey image of the
giant radio galaxy GRG 0503-28 at 70-230 MHz has revealed an
inversion-symmetric bending of its two lobes, while maintaining between their
bent portions a ~200 kpc wide strip-like radio emission gap. This lends the
source the appearance of a mega-sized X-shaped radio galaxy. Identifying the
emission gap with the presence of a gaseous layer, probably a WHIM-filled sheet
in the cosmic web, we suggest that the layer is the most likely cause of the
inversion-symmetric bending of the two radio lobes. Multiple observational
manifestations of such gaseous layers are noted. The two lobes of this GRG,
known to extend very asymmetrically from the host galaxy, are remarkably
symmetric about the emission gap, confirming a curious trend noted earlier for
double radio sources of normal dimensions. The anomalous radio spectral
gradient reported for the northern lobe of this GRG is not substantiated.
