Suspension of disbelief doesn't go *this* far.
This is a truly awful film. The whole "earth-killing asteroid" has been done a few times, presenting some just-about-plausible solutions to the problem.
This film requires an complete suspension of disbelief. Not just the ending bit, but the whole sorry chain of events that lead up to the heroes saving the day.
The script is weak. The acting is weak. The special effects are weak. Please, for the sake of your own self-respect, do not waste 90+ minutes of your life on this bilge.