NASA gets set to crash spacecraft into asteroid

STORY: NASA wants to find out if it can push an asteroid off a doomsday collision course with Earth by crashing a spacecraft right into it.

Consider it the world’s first test for world's first planetary defense system

Andrea Riley is a program executive for the Double Asteroid Redirection Test, or DART.

“We're constantly looking in the skies for potential new asteroids and threats… so this test will help, you know, give us confidence that we do have a mitigation strategy should a threat ever be identified."

The spacecraft launched last November from California.

Its target: a "moonlet" called Dimorphos which is about the size of a football stadium.

The mission will test the spacecraft's ability to alter the asteroid's trajectory with sheer kinetic force, plowing into it at high speed to nudge the space boulder off course just enough to keep our planet – at least theoretically- out of harm's way.

Dimorphus poses no actual threat to earth and is tiny, especially in comparison to the asteroid that hit 66 million years ago, leading to the extinction of the dinosaurs.

But DART coordination lead Nancy Chabot says smaller ones are more common and theoretically a bigger concern.

“…the regional devastation could be the size of a city or a small state or a small country, and so it is very devastating - very rare, no known threat - but that's why the focus a lot of times is on objects of that size, and why Dimorphos is such a perfect target for this first planetary defense test mission.”

Cameras on the spacecraft and a smaller one nearby will capture all the action, up to one-and-a-half seconds before impact, says system engineer Elena Adams ...

"You really are seeing it real time. You're seeing that impact."

The mission’s big finale is set to take place on September 26.

For DART mission engineer Michelle Chen, it can’t come soon enough...

"We are so excited about it. It's two weeks away. So, now my heart rate has increased a little bit (laughs)."