Space VLBI observations of 3C 371

We present the first space VLBI observations of 3C 371, carried out at a fr equency of 4.8 GHz. The combination of the high resolution provided by the orbiting antenna Highly Advanced Laboratory for Communications and Astronom y (HALCA) and the high sensitivity of the VLBA allows imaging of the jet of 3C 371 with an angular resolution of approximately 0.26 mas, which for thi s relatively nearby source corresponds to similar to 0.4 h(-1) pc. Comparis on between two epochs separated by 66 days reveals no apparent motions in t he inner 7 mas jet structure above an upper limit of similar to 1.4 h(-1) c . This value, the absence of detectable counterjet emission from the presum ably symmetric jet, plus the presence of an extended double-lobe structure are consistent with the knots in the jet being stationary features such as standing shocks. The jet intensity declines with the angular distance from the core as phi(-1.68). This is more gradual than that derived for 3C 120, phi(-1.86), for which there is evidence for strong interactions between the jet and ambient medium. This suggests that in 3C 371 there is a greater le vel of in situ acceleration of electrons and amplification of magnetic fiel d. We interpret sharp bends in the jet at sites of off-center knots as furt her evidence for the interaction between the jet and external medium, which may also be responsible for the generation of standing recollimation shock s. These recollimation shocks may be responsible for the presumably station ary components. The radio properties of 3C 371 are intermediate between tho se of other radio galaxies with bright cores and those of BL Lacertae objec ts.