What makes sense, DA, is the knowledge.
The knowledge we have of the Universe, of the Earth and of ourselves, we owe it to countless people who figured out what was going on. We stand on the shoulders of giants. Something like the Apollo program brought us a considerable knowledge of the Moon and of our planet as seen as a planet (32 years ago tonight, BTW) but the human adventure has mainly inspired those who were there to witness it. The scientific knowledge will never be lost and we will gain more knowledge through what we already have learned. Robots are a formidable knowledge tool. The thrill, the adventure, the experience of a manned mission are lasting for only a short while, but the knowledge lasts as long as mankind will last.

Raoul