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We present new Very Long Baseline Interferometry observations of the LINERgalaxy NGC 4278. The observations were taken with the Very Long Baseline Array(VLBA) and a single antenna of the Very Large Array (VLA) at 5 GHz and 8.4 GHzand have a linear resolution of <0.1 pc. Our radio data reveal a two sidedstructure, with symmetric S-shaped jets emerging from a flat spectrum core. Wefit the jet brightness with gaussian components, which we identify from aprevious observation taken five years before. By comparing the positions of thecomponents in the two epochs, we measure motions between 0.45 +/- 0.14 and 3.76+/- 0.65 mas, corresponding to apparent velocities < 0.2c, and to ages in therange 8.3 - 65.8 years. Assuming that the radio morphology is intrinsicallysymmetric and its appearance is governed by Doppler beaming effects, we findthat NGC4278 has mildly relativistic jets (beta ~ 0.75), closely aligned to theline-of-sight (2 degrees < theta < 4 degrees). Alternatively, the source couldbe oriented at a larger angle and asymmetries could be related to the jetinteraction with the surrounding medium. We also present new simultaneous VLAobservations between 1.4 and 43 GHz, and a 5 GHz light curve between 1972 and2003. The radio spectrum can be fit by a relatively steep power-law (alpha =0.54). We find significant variability at 5 GHz. All these arguments indicatethat the radiation from NGC 4278 is emitted via the synchrotron process byrelativistic particles accelerated by a supermassive black hole. Despite a muchlower power, this is the same process that takes place in ordinary radio loudAGNs.Comment: 29 pages, 9 figures, ApJ accepte

The Two‐sided Parsec‐Scale Structure of the Low‐Luminosity Active Galactic Nucleus in NGC 4278