Once we discover alien life out there, humanity will never be the same.
Finding an alien civilization will change humanity dramatically, but not so much in the obvious ways. Will we interact, trade, learn from one another's technology, or start intergalactic wars? None of that is highly likely, mostly for logistical reasons. Bill Nye thinks that the change will be more of an internal, philosophical, and spiritual change. What will it mean for humans to not be the only living thing in the cosmos? Many of us want to know and so, operating on just a small budget running in the background of all other scientific pursuits, there are astronomers and physicists continually looking and listening for life out there so that we may one day be able to ask ourselves that very question. Bill Nye's most recent book is Unstoppable: Harnessing Science to Change the World.
It seems inevitable that there will be a Mars colony, but the path there won't be easy. There are two key challenges ahead that will push innovation.