Answer:
I am a path between high natural masses; remove the first letter to get a path between man-made masses.
Every dawn begins with me. At dusk I'll be the first you see and daybreak couldn't come without. What midday centers all about. Daises grow from me I'm told. And when I come I end all code but in the sun I won't be found. Yet still each day I'll be around.
What gets bigger the more you take away?
I am not a toy though many use me for pleasure. I have a butt but I cannot poo.
I can fly but I have no wings. I can cry but I have no eyes. Wherever I go darkness follows me.
What is always coming but never arrives?