I'm afraid YOU are the one that should be working for Hollywood.
Have you calculated how large a mass one needs to divert an asteroid???
Where are you going to get this large mass?
Yes - we've heard of gravitational force; and we also know that the gravitional
force is the WEAKEST of all the primordial forces.
Your suggestion is ridiculous. If you had rockets that were powerful enough to boost
enough mass to deflect the asteroid, then you could just use those rockets,
themselves to push the asteroid.
Any energy you put into deflecting the asteroid via gravity, essentially
ultimately came from energy of the rockets that put your large mass in
the vicinity of the asteroid. So why not use those rockets directly?
That way you won't have wasted the residual gravitational potential energy
that will be in the mass after it deflected the asteroid.
Additionally, we don't have rockets that are that powerful.
In order to divert a large asteroid; we need to alter its course; and that is going to
take a good deal of energy. The most compact way of transporting energy to the
asteroid is to transport it as nuclear energy!!!
Pound for pound, nuclear energy is about 1 Million times more "energy dense" than
any type of chemical energy.
This was all very thouroughly discussed / studied over 10 years ago at the
Planetary Defense Workshop that I refer to above.
Dr. Gregory Greenman