Supporters of human space exploration say that the benefits of sending people into space far outweigh human spaceflight's great cost, even if some of those benefits aren’t as easy to measure as money.
The achievements of putting men and women into space and then safely bringing them home again are a source of pride and inspiration for humanity. As President Kennedy once put it, the goal of space travel is, in part, “to serve to organize and measure the best of our energies and skills.” Many believe that nothing focuses our scientific efforts and marks its triumphs more than the challenges of putting humans in space.
Proponents also argue that a single human can perform thousands of extremely varied tasks, and while a machine can only respond to the situations its programmers prepared it for, humans can adapt, using intuition and creativity to solve unexpected challenges.
But human astronauts also have their downsides ...