Conclusions
- RSG models show large high-contrast convective surface features.
- Schwarzschild's scaling argument is essentially OK.
- Important role of radiative/convective time scales.
- "Granules" on Betelgeuse/Sun have different properties.
- Difference Betelgeuse/Sun is consistent with general trends in models.
Outlook
- Lower atmosphere: OK, but:
- Higher resolution: small features, temperature structure, microturbulence
- Non-grey opacity tables: temperature structure
- Upper atmosphere: no wind, yet, but:
- Dust (in extended models, AGB & RSG)
- Radiation pressure
- Rotation
- Magnetic fields
- NLTE
Things to do -- now
