If you're standing or lying down, I'm nowhere to be found. I am also a type of licky dog. If you make the dog sit, and you do too, Only then will I appear. What am I?

Round and round I go Where will I stop? Nobody knows. Sometimes I have horses and carriages, Other times mythological beasts or you feel like you've gone to the zoo.

From rooftops I may often hang, silent, cold, and sharp as a fang. Though made of water, I feel like stone, In winter’s grasp I’ve slowly grown.

I’m a tiny drop of ink from the summer sun, Multiplying on your nose when the winter's done. A constellation on your skin, I love the outdoor light, But hide away in shadows and fade out of sight.

I am never still, yet I go nowhere. I cover more than half the world, yet fit in no map's margin. I hold the sky's reflection but own no mirror. Kings have crossed me, none have conquered me yet. What am I?