Heat Transfer in Solids (motion of objects inside a domain)

Hi,

I am trying to model a simple 2D transient heat transfer problem. For this I move a sphere with a constant boundary temperature trough a plane making use of the Deformed Mesh and the Heat Transfer in Solids Interfaces. But what I can not understand is...

1. Is it possible to move the sphere through the plane, if the both are solid (... does FEM allowed this motion)?

2. How does Comsol calculate the temperature in the space left of the overlap area between the time steps? Diffusion? (see attachment!)

best regards,

Antoni Artinov