One thing I have always believed, that science has ignored, is that when humanity has a strong enough desire to reach the unreachable, God helps a bit. It gives the human mind an unquenchable thirst to seek answers, and in time, we do. We evolve when our solutions are past, into new and exciting possibilities, so never fear not understanding nothing is impossible.
In the long term, I suggest developing probes to seek out sustainable planets, as we are using Earth up at pace that even quantum physics find hard to predict. We must work for humanities future and save all we have accomplished of our past.