We talked about it in the Genre and era thread but noting conclusive came out of the thread concerning this topic
This is the thread to discuss (quote form Wikipedia):

Astrophysics (from Greek astron, ἄστρον "star", and physis, φύσις "nature") is the branch of astronomy that deals with the physics of the universe, including the physical properties of celestial objects, as well as their interactions and behavior. Among the objects studied are galaxies, stars, planets, extrasolar planets, the interstellar medium and the cosmic microwave background.

So… for those that don’t want an earth like planet, this is the place to talk about it.

Star: how many, what size?
Planet: distance from the sun, tilting angle, size, magnetic field, number and size of moons, speed of rotation, atmospheric composition…
Other planets: for those that are interested in developing the rest of the star system
Constellations and everything out of the system: it could be an area for development