NASA's launched a potentially ground-breaking mission - as an unmanned spacecraft took off from Florida's Cape Canaveral.
It's heading to collect dust and gravel from the surface of an asteroid, bringing samples back in a couple of years.
Scientists say there's a slim chance the asteroid could crash into Earth in about 150 years.
Professor Dante Lauretta, the Head of Planetary Science and Cosmochemistry at the University of Arizona's Lunar and Planetary Laboratory says everything's gone to plan: "You'll be real glad to know that everything went absolutely perfect. This represents hopes and dreams, the hard work, the blood, sweat and tears of thousand and thousands of people."
Our @OSIRISREx spacecraft is on its way, and everything is on the timeline. Keep watching: https://t.co/KX5g7zfYQe pic.twitter.com/89uZ54af0v
— NASA (@NASA) September 8, 2016
The asteroid, named Bennu, was chose because of its composition, size, and proximity to Earth. Bennu is a rare B-type asteroid and ich is expected to have organic compounds and water-bearing minerals like clays.
Bennu is next expected to pass by Earth in 2135, when it will pass just inside the moon's orbit, and this close approach will change Bennu's orbit, and scientists say that could cause it to impact Earth sometime between 2175 and 2199.