Space Exploration Costs the Same as Exploring the World

The Solar System is much vaster than the Earth, but the speeds of our spacecraft are, of course, much greater than the speeds of the sailing ships of the fifteenth and sixteenth centuries. The spacecraft trip from the Earth to the Moon is faster than was the galleon trip from Spain to the Canary Islands. The voyage from Earth to Mars will take as long as did the sailing time from England to North America; the journey from Earth to the moons of Jupiter will require about the same time as did t...