An Halpha image of the nebula about PSR~0437-4715. The arrow points in the direction of the pulsar proper motion derived through timing (after a small correction has been applied for solar motion with respect to the local standard of rest and differential galactic rotation). The faint star directly behind the shock is the white dwarf companion of the pulsar. The distance between the pulsar and the leading edge of the Halpha emission is about 1400 AU. On this scale, the position of the pulsar is indistinguishable from that of its companion.
The numerical solution to the shock equation is superposed on the image. Three parameters of the shock were varied to obtain this fit: the standoff distance, the position angle on the sky, and the inclination out of the plane of the sky. The solution shown here implies that the pulsar motion is out of the plane of the sky at an angle of about 37 degrees. The difference in fitted position angle and that obtained from pulsar timing is within the known timing errors.
