Neutron Stars
Links
Windows to the Universe: Neutron Stars
http://www.windows.ucar.edu/cgi-bin/tour_def/the_universe/NS.html
A typical neutron star is the size of a small city, but it may have the mass of as many as three suns.
X-ray Astronomy: Neutron Stars
http://imagine.gsfc.nasa.gov/docs/science/know_l1/neutron_stars.html
Brief description of neutron stars.