Vela Pulsar (PSR B0833-43): there is a nebula that is possibly due
to a jet extending to the SW.  The PA of this extended emission is
about 155deg W of North.  Since we have proposed to read out
the CCDs in continuous clocking mode, the optimum roll angle
is probably equal to this angle +/- about 40 deg, for a range
of -60 deg (E of N) to 20 deg (W of N) and the same angles
with 180 deg added (120-200 deg W of N).