This photo realistic, fully detailed, stunning looking Earth was created in Blender 2018 (v2.79). The Earth itself is bumb mapped as well as the clouds with those settings easily editable in the node editor. The textures used are right around 8K and would be super easy to swap out the current textures with higher resolution one.
There are 3 different textures; Earth, Clouds, and Atmosphere. Each one of those have their own objects in the mesh to create distances between the layers to make it even more realistic.
The .png file is exported in 4K.
Anything on the object is super easily adjustable such as size, resolution, atmospheric color, and distances between the clouds and the atmoshphere.
Because of the spherical shape, there is no reason to unwrap the object.