NASA asteroid redirection test set to launch from Vandenberg tonight

If all goes as planned, the Double Asteroid Redirection Test spacecraft will travel at a speed of roughly 15,000 mph and ultimately crash into Dimorphos, a moonlet asteroid which orbits larger twin asteroid Didymos, by the fall of 2022, according to NASA launch officials. 

The Didymos binary asteroid system is the ideal candidate for DART, according to officials, as it poses no actual impact threat to Earth, and scientists can measure the change in Dimorphos’ orbit with ground-based telescopes. Outcomes of the mission will demonstrate a potential method of protecting Earth from hazards in the future, officials said.

Col. Rob Long, Space Launch Delta 30 commander, will be the launch decision authority on-site at Vandenberg's eastern Space Launch Complex-4. 

A live webcast of the mission will begin approximately 15 minutes prior to liftoff at NASA TV or at SpaceX.com.