Detail this asset from Unity Asset Store: https://assetstore.unity.com/packages/3d/environments/sci-fi/planets-60740
But now you can download Planets FREE.
! New price for a limited time !
50 Cents per Planet.
When buying this, you get access to a complete, editable and customizable planet shader, 20 sets of planet textures, Multiple clouds and cities textures, a 3D star, a 2D star and a space skybox
– Runs smoothly on mobile and console
– Adjustable atmosphere and sub atmosphere (color/size/spread)
– Independant ambiant light control
– Additional shader with transparency where the planet is not lighted ( for daylight scene where the planet is in the sky )
– Clouds are moving/occluding
– Cities appears on land and in the dark
– A flow map that animate the texture for the star
4 new additional hi-res planets for the same price
I strongly suggest you to open the Readme for additional informations
unityassetcollection.com – Get all paid Unity Asset for free