Alliance are a serie of different mods. On the Star Wars GC, you can play the civil war Empire vs Rebel era + Black Sun and soon the Republic and CIS.
M'haeli is a temperate new planet covered by snow in more parts than other temperate planets, by this reason I have added this special texture.
However as many other things and because clearly the game can not support one texture for each planet, one texture for each nebulae, one texture for each star system because at the end, all would be overloaded, the textures are shared by other planets and nebulae, specially the nebulae are shared by each cluster of planets.