... Find out the orbital parameters of the planets around PSR B1257+12 . Why doesn't PSR B0655+64 follow the core mass radius relation . Estimate the change in the dispersion measure between orbital phases 0.30 and 0.40 for PSR B1957+20 (see the delay curve in the notes). Use your answer to estimate the change in the column density of electrons. Estimate the orbital velocity of 2 neutron stars in a 2 hour orbit with a radius of 0.5 light seconds. ...