Illuminating a tadpole's metamorphosis III: quantifying past and present
  environmental impact
  We combine MUSE and ALMA observations with theoretical models to evaluate how
a tadpole-shaped globule located in the Carina Nebula has been influenced by
its environment. This globule is now relatively small (radius ~2500 au), hosts
a protostellar jet+outflow (HH 900) and, with a blue-shifted velocity of ~10
km/s, is travelling faster than it should be if its kinematics were set by the
turbulent velocity dispersion of the precursor cloud. Its outer layers are
currently still subject to heating, but comparing the internal and external
pressures implies that the globule is in a post-collapse phase. Intriguingly
the outflow is bent, implying that the YSO responsible for launching it is
comoving with the globule, which requires that the star formed after the
globule was up to speed since otherwise it would have been left behind. We
conclude that the most likely scenario is one in which the cloud was much
larger before being subject to radiatively-driven implosion, which accelerated
the globule to the high observed speeds under the photoevaporative rocket
effect and triggered the formation of the star responsible for the outflow. The
globule may now be in a quasi-steady state following collapse. Finally, the HH
900 YSO is likely $\gtrsim$1 M$_{\odot}$ and may be the only star forming in
the globule. It may be that this process of triggered star formation has
prevented the globule from fragmenting to form multiple stars (e.g., due to
heating) and has produced a single higher mass star.
