First it should be mentioned that this method is useful only for those cases when the planet is shown at the middle or background.

1. Create the scene in 3D MAX
2. In Geometry --> geosphere create a spheresized 132 (it is not important what size it will be, it's up to you to decide)
3. Duplicate it twiceincreasing the size by1% with each duplicating
4. The final sequense of spheres will be named accordingly: surface-the surface of the planet; cloud-the layer of clouds(if you want a more realistic view, create several layers); atmosphere-the atmosphere.