I have to disagree with the answers given so far, although lone77star is partially correct, at least in my own humble (humble?) opinion.
On the science front: slowly scientists are seeing more and more answers related to light and energy.
Spiritually, as well as on the soul level, I feel that as a species we will continue to evolve over a long period of time towards enlightenment. We recently went into a new shift in energy and enlightenment, which started back in the 70s and 80s. That's just the beginning.
I don't think that humans will cease to exist. We'll continue to be here for a very long time, as Earth is a central hub for spiritual growth before our souls move on to the next level.
However, I do think that eventually we will reach out into the solar system, once we reach the next stage of enlightenment, which may come sooner than some think. Or later. It really depends on what happens, but I think in the next couple hundred of years, we as a species will begin to unlock the secrets of fast space travel, and begin to think about seriously inhabiting other worlds in perhaps 3 or 400 years from now.
Oh, as for the God thing, religion will always have its place, but will evolve over time.