Questions about the ultimate beginnings

People have always wanted to know the answers for the questions:

How did it all start?

Was there anything before our universe?

Is our universe changing? And if yes, how is it changing?

How old is our universe?

How big is our universe?

How can we study it?

Are we the only planet it in?

If there are other planets, are there some kinds of life?

and many, many others...

Astronomy and cosmology, two basic sciences studying the universe and its laws, have already given us many answers. They also bring far more new questions. 

Let's study this fascinating area together...