Exploration of any kind is like stepping into a dark room. It’s unpredictable. It can be a little bit scary and maybe even dangerous—but it is ultimately about potential. Prehistoric Asians crossing the land bridge to North America and Europeans setting out to circumnavigate the globe were stepping into that dark room of exploration; all of them had more questions than answers. And all their explorations pushed back the frontiers of human knowledge and accomplishment.

New exploration challenges have always produced new human developments. Longer sea journeys required technological advances in ship design and new life-support systems, such as methods for preserving food for extended voyages. As humans increased the distances between themselves and those they left behind, reliable, faster communications had to be developed, whether through better roads, Pony Express, or telephone.

Space exploration brings the same twin promises of challenge and development. When NASA needed to power spacecraft with unlimited energy, it took the lead in developing solar energy technology. To study Earth’s ozone layer from satellites, NASA’s Jet Propulsion Laboratory came up with a low-temperature laser that is now uniquely capable of vaporizing coronary artery blockages without damaging tissue. A buoy-shaped life raft, a descendant of rafts developed for the Apollo program, has saved hundreds of lives on the high seas.

The technological benefits of space exploration seem endless: computer readers for the blind, virtual reality devices, lightweight aerospace composite materials, aircraft lightning protection, x-ray imaging systems, vehicle-collision-avoidance systems, corrosion-resistant sealants, even cordless tools and vacuum cleaners.

There is no way to count the number of lives saved each year through space-based weather monitoring. And as we learn more about the effects of space on the human body—as was the focus of John Glenn’s recent flight—we may well learn ways to improve and preserve human life on Earth. In the weightless environment of space, for instance, bacteria and cancer cells grow in larger, looser shapes than on Earth, enabling scientists to study their structure and development more easily.

On the other hand, I have spent the past few hundred words making what is, for me, perhaps the least compelling argument in favor of space exploration. The fact is, we belong in space, just as we belong in New Jersey. I don’t believe humans have ever viewed their home planet quite the same since that Christmas Eve in 1968 when Apollo astronauts first viewed Earthrise above the lunar surface. When we look out on a night sky, we now know we are gently bathed in the light of stars that died before our Earth was even formed. We are a part of that. The universe is not out there. It is our home address.