Summary: The Penrose limits of a D5-brane wrapped on the sphere of \(AdS_{5} \times S^{5}\) and connected to the boundary by \(N\) fundamental strings, which is dual to the baryon vertex of the \(\mathcal N= 4\) \(SU(N)\) super Yang-Mills theory, are investigated. It is shown that, for null geodesics that lead to the maximally supersymmetric Hpp-wave background, the resulting D5-brane is a 1/2-supersymmetric null brane. For an appropriate choice of radial geodesic, however, the limiting configuration is \(1/4\)-supersymmetric and closely related to the Penrose limit of a flat space BIon.