  As the presumed remnant of SN1181, 3C 58 houses one of the youngest known
neutron stars in the Galaxy. The properties of this young pulsar and its
associated wind nebula differ considerably from those of the Crab, and may well
offer a more typical example of the endpoint of massive star collapse. High
resolution X-ray studies reveal structures in the inner nebula that may be
associated with the pulsar wind termination shock, a jet that may be aligned
with the rotation axis, and other regions of enhanced emission. Spectral
variations in the PWN are consistent with the expected evolution of the
postshock flow, and complex loops of emission are seen in the nebula interior.
Limits on the NS surface temperature fall below standard cooling models,
indicating that some more rapid neutrino cooling process is required. The outer
regions of 3C 58 show thermal emission with enhanced levels of Ne, indicative
of shocked ejecta bounding the PWN.
