  We calculate the radiative properties of Sagittarius A* -- spectral energy
distribution, variability, and radio-infrared images -- using the first 3D,
physically motivated black hole accretion models that directly evolve the
electron thermodynamics in general relativistic MHD simulations. These models
reproduce the coupled disc-jet structure for the emission favored by previous
phenomenological analytic and numerical works. More specifically, we find that
the low frequency radio emission is dominated by emission from a polar outflow
while the emission above 100 GHz is dominated by the inner region of the
accretion disc. The latter produces time variable near infrared (NIR) and X-ray
emission, with frequent flaring events (including IR flares without
corresponding X-ray flares and IR flares with weak X-ray flares). The photon
ring is clearly visible at 230 GHz and 2 microns, which is encouraging for
future horizon-scale observations. We also show that anisotropic electron
thermal conduction along magnetic field lines has a negligible effect on the
radiative properties of our model. We conclude by noting limitations of our
current generation of first-principles models, particularly that the outflow is
closer to adiabatic than isothermal and thus underpredicts the low frequency
radio emission.
