Gravitation is a force human kind encounters everywhere, one which remained unconquered for the vast part of human existence.
When physicists look at gravitational fields, they consider all objects within a given field to have negative energy to indicate their captivity in that gravitational field. If an object has exactly enough energy to escape that field, it has 0 energy. In essence when it goes beyond that 0, it becomes free from the gravitational system. This bit describing the rocket's ascent at the very end made me think of a possible explanation for what constitutes going "beyond the zero":
"This ascent will be betrayed to Gravity. But the Rocket engine, the deep cry of combustion that jars the soul, promises escape. The victim, in bondage to falling, rises on a promise, a prophecy of Escape" (774). The rocket technology serves as a perfect symbol for escaping the system; it promises mankind the ability to free himself from the gravitational field which constantly surrounds him. Just as the end of the war gave man a promise of escape from the suffering of the previous eras, the rocket rises with the chance of transcending the old system only to fall back under its own influence. The idea of betrayal ultimately lies at the feet of the men who engineered the rocket and used it only to enhance their power. In the midst of all this, the victim, Gottfried, the one who lies at the heart of the system and makes it all possible (see p765 where Gottfried effectively "mated" the rocket to complete it) stands for the preterite who will meet their end until the leaders fulfill the prophecy and one preterite who wouldn't die will validate their deaths for this cause.

I think film plays such an important role because it is a way of creating the illusion of continuous motion without having to lie at the absolute zero. In the very final moment, Pynchon freeze frames the final infinitessimally small moment and yet "there is time" (775) leaves a sense of an almost infinite second carved out of nothing for man to make his choice, the opportunity to escape his system. This ties into the idea of spiritual continuity after death evoked by the quote leading off Part 1 "Everything science has taught me, and continues to teach me, strengthens my belief in the continuity of our spiritual existence after death" p1 said no less than by the man who built the rocket and worked on later US Space projects. Can Technology (with a capital T) ultimately deliver us to some sort continuity, some sort of freedom beyond the everpresent system?

Random, but:
As an LA native I was really entertained by the last paragraph on page 770: "The Santa Monica Freeway is traditionally the scene of everyform of automotive folly konwn to man," at least I know for sure now that Pynchon got something right.