This has been a problem for Gimp - I don't think anybody knows how to make things explode....
This was done with Aviutil on Windows. It handles the explosion parameters like speed and gravity of falling bits. I think background is also relevant.
The video didn't really show an exploding planet but it's condition prior to disintegration.
After watching the news on TV tonight I feel like I'm living on an exploding planet anyway. We had a population explosion, now it seems to have turned into a population implosion.