The future of the human race—if there will be a future—is out in space. Assuming we can capture and harvest comets containing the requisite elements, i.e. carbon, hydrogen, oxygen and nitrogen—CHON—we can create food away from the Eden-like paradise we call Earth. Earthlings require air, food and water. Plants provide two out of three. Comets provide the last. If you want real space exploration, it all starts with lassoing a CHON comet. I'll leave the mechanics of that to NASA, but many people believe it can be done. Once we have a CHON asteroid or comet in Earth orbit, the space race will at long last, truly be underway.
Danger number one is the Sun. It regularly bombards the solar system with thick blankets of radiation. What this means, is that without protection, humans in space will die faster than a gerbil in a microwave. Interestingly enough, something as simple and as common as H2O can protect humans from this regularly emitted cloud of Sun wrath.
Once you have your habitat ready—I envision a spinning hamster-wheel-like vessel filled with water, harvested from your tame Earth orbiting comet—you need a food source. It must be energy rich. It must grow in water. It must convert CO2 into oxygen. If I'm a geneticist, I'm thinking kelp and wheat. Seawheat. Feed the Earth. End world hunger. Feed the astronauts up in Waterworld. Win win win win win!