  R Aquarii is a symbiotic binary surrounded by a large and complex nebula with
a prominent curved jet. It is one of the closest known symbiotic systems, and
therefore offers a unique opportunity to study the central regions of these
systems and the formation and evolution of astrophysical jets. We studied the
evolution of the central jet and outer nebula of R Aqr taking advantage of a
long term monitoring campaign of optical imaging, as well as of high-resolution
integral field spectroscopy. Narrow-band images acquired over a period of more
than 21 years are compared in order to study the expansion and evolution of all
components of the R Aqr nebula. The magnification method is used to derive the
kinematic ages of the features that appear to expand radially. Integral field
spectroscopy of the OIII 5007A emission is used to study the velocity structure
of the central regions of the jet. New extended features, further out than the
previously known hourglass nebula, are detected. The kinematic distance to R
Aqr is calculated to be 178 pc using the expansion of the large hourglass
nebula. This nebula of R Aqr is found to be roughly 650 years old, while the
inner regions have ages ranging from 125 to 290 years. The outer nebula is
found to be well described by a ballistic expansion, while for most components
of the jet strong deviations from such behaviour are found. We find that the
Northern jet is mostly red-shifted while its Southern part is blue-shifted,
apparently at odds with findings from previous studies but almost certainly a
consequence of the complex nature of the jet and variations in ionisation and
illumination between observations.
