Re:Incomplete summary (Score 1)

I wonder if anybody's got a model worked out yet to explain how a narrow planar beam gets generated.

relativistic beaming or aberration. if an object, emitting light isotropically (equally in all directions) is traveling very fast (close to the speed of light) relative to the observer, the emitted light appears to be 'beamed' forward in the direction that the emitting particle is traveling. the faster the emitting object is traveling, the narrower the beam. the featured article doesn't mention it, but i imagine this is the explanation for the beaming of this radio emission.