A one-sided knot ejection at the core of the HH 111 outflow
  We present an astrometry study of the radio source VLA 1 at the core of the
HH 111 outflow using new data (2007) as well as archival observations
(1992-1996). All data were taken at 3.6 cm with the Very Large Array in its
most extended (A) configuration. The source VLA 1 has undergone a dramatic
morphological change, showing a one-sided knot ejection in the 2007 epoch. We
also report on the detection of a 3.6 cm compact continuum source (VLA 3)
located at (-10.6",98.7") from VLA 1. No significant absolute proper motions
were found for VLA 1 and VLA 3 and the upper limits are consistent with those
found for (embedded) radio sources in the Orion Nebula. We favor the
interpretation that in the continuum at 3.6 cm we are observing two nearly
perpendicular jets. HH 111 presents a new case of one-sided jet ejection in a
young stellar object. The Galactic (or extragalactic) nature of VLA 3 remains
unclear.
