Viewpoint: Yes, the spirit of space exploration as an effort for all humanity demands broad participation by astronauts, scientists, and civilians alike.

Viewpoint: No, space exploration—currently in its infancy—is an inappropriate pursuit for civilians unused to, or unfit for, the rigors and risks that it poses.

Exploration is as old as mankind. Our earliest ancestors explored out of necessity, whether as hunter-gatherers looking for food, for ample space to live, or simply out of curiosity. Settlement of Earth went quite slowly. If early humans evolved in Africa 2 million years ago, it took their descendents 1.99 million to find North America, since evidence of early human activities in what is now the United States only dates back some 12,000 years. Rapid mass transportation in the form of trains, cars, and aircraft had to wait until the nineteenth...