Riddles

Since it's almost midnight, I decided to post some riddles. I'll post the answers later, if anyone can't guess.

What fills the night and every room till a window is opened to chase out the gloom?

I wind my way through hills and plains
and go as do the falling rains
the mountains high are where I start
Where I am born from winters heart
And all the world knows where I go
through valley wide to ocean low
What Am I?

The light I bring is rivaled not
by stars, by moon, by earth
and by me have the ancients sought
the measure of their worth
I shine by day, I sleep by night
Though clouds may hide my face
Naught shall disturb my ancient flight
Above the sky in blackest space
What Am I?