"Alex Kudrasev" wrote in message
...

"Greg Neill" wrote in message
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"Bill Nunnelee" wrote in message
arthlink.net...
The speed of the star is much less than the speed of light, so there's
no
possibility that photons arriving from different points along the star's
trajectory would arrive at the same time.


True. On the other hand, jets from active galaxies are
moving at a significant fraction of the speed of light,
and if the geometry is right with respect to source and
observer, will appear to be moving superluminally.


So I take it that we can observe 'streaks' (they appear as lines) in fast
moving light sources?

Well, jets are more or less continuous in nature, sometimes
with lumpy inclusions. But I can't think of a geometry for
the source and observer that would have light from different
points on the trajectory of the same "lump" arrive at the
same time at the observer.