Question

What is conduction in stellar atmospheres?

Answer 1

Transfer of heat energy by physical contact of stellar materials. Current models do not assume any conduction in stellar atmospheres.

Explanation:

Heat transfer can take place by conduction – physical contact of solids, convection – transfer by moving molecules of gases (also usually involves conduction to the gases from the source and from the gases to the object), and radiation – direct energetic transfer by electromagnetic radiation.

Current stellar models assume all heat transfer is primarily by radiation, with negligible convection (in cooler stars) or conduction contributions. https://arxiv.org/pdf/astro-ph/9906130v1.pdf ; http://www.ifa.hawaii.edu/users/kud/teaching/4.Convection.pdf