Here is a 1 minute 39 second teaser of "Planetary Defense". The full duration will be 48 minutes.

A 48 minute documentary "Planetary Defense", about efforts underway to detect and mitigate an impact with Earth from asteroids and comets, collectively known as NEOs (Near Earth Objects).

"It's not if (an impact will happen), it's when!"

The one minute "Planetary Defense" teaser (playing) features David Morrison, Duncan Steel, General Pete Worden (USAF) and Michael Belton. The documentary will feature them and many more experts in the field of Near Earth Object impact hazard mitigation including Sir Arthur C. Clarke.

http://spaceviz.com/documentaries/planetarydefense/planetarydefense.html