the david h. koch fund for science, supportinova and promoting public understanding of science. and the corporation for public broadcasting. and by pbs viewers like you-- thank you. and millicent bell, through the millicent and eugene bell foundation. since the dawn of humanity, we've looked to the heavens and wondered, how old is the universe? how many stars are there in the sky? are there other planets out there like our own? but in the last 25 years, there's been a revolution... all because of a machine called hubble. traveling in space, high above the distortions of our atmosphere, gives this giant telescope great power. matt mountain: it's t size of a school bus. it's traveling at 17,000 miles an hour. it's 300-and-something miles above your head. but in there is onof the most precise mirrors mankind has ever built. narrator: billions of times more sensitive than our own eyes, the space telescope has literally brought the universe to us, making more than a million observations. one legendary image is called the "pillars of creation." it's a giant plume of gas and dust where