  We present a numerical simulation of the formation of a massive star using
Monte- Carlo-based radiation hydrodynamics (RHD). The star forms via stochastic
disc accretion and produces fast, radiation-driven bipolar cavities. We find
that the evolution of the infall rate (considered to be the mass flux across a
1500 au spherical boundary), and the accretion rate onto the protostar, are
broadly consistent with observational constraints. After 35kyr the star has a
mass of 25 solar masses and is surrounded by a disc of mass 7 solar masses and
1500 au radius, and we find that the velocity field of the disc is close to
Keplerian. Once again these results are consistent with those from recent
high-resolution studies of discs around forming massive stars. Synthetic
imaging of the RHD model shows good agreement with observations in the near-
and far-IR, but may be in conflict with observations that suggests that MYSOs
are typically circularly symmetric on the sky at 24.5 microns. Molecular line
simulations of a CH3CN transition compare well with observations in terms of
surface brightness and line width, and indicate that it should be possible to
reliably extract the protostellar mass from such observations.
