What is Natural Theology? I would define it as how God has revealed himself through nature. If such a statement makes you recoil and shout, "But what about the Bible, isn't it enough?," then let us start with Psalm 19:1 among others.
The heavens declare the glory of God; and the firmament sheweth his handywork.
I think we can find out something about God through nature. It will never be enough since God has revealed himself for us through Jesus. But just because nature can't tell us everything about God doesn't mean it can't tell us anything about God.
I watched a show the other night, How the Universe Works. It was all about stars and how if there were no stars there would be no life. It was estimated that on a clear night, one could possible see 3,000 stars, but the actual number of stars in our galaxy alone could be more than 100 billion, that is 100,000,000,000. Our Sun is just one of those.
Inside stars is a bakery for cooking up elements that are needed for life (i.e. carbon, oxygen, and most importantly iron). There is no other way of getting these elements than from stars.
So, what conclusions can one draw? I think I would say that God created the stars to shine, to bring light and life into his world. He gave humanity the ability to see the stars and study them and by understanding them, we see God's vastness, power, and creativity. He even knows their name! (Psalm 147:4 and Isaiah 40:26)