Electron-Positron Jets in the Quasar 3C 279?

This map shows the overall strength (contours) and circular polarization (colored oval) of radio waves from quasar 3C 279, whose powerful plasma jet runs from upper left to lower right. Taken with the Very Long Baseline Array, the data has given astronomers a handle on the jet's makeup.
(Wardle, Homan, Ojha, & Roberts 1998 - Nature, vol 395, pg 457; image appeared in Sky & Telescope, March 1999)