These disadvantage and benefits can be reliably expected. The remaining benefit is more speculative because it involves human psychology. What will be the effects on human thinking of large-scale space tourism, space art, space sport, and expanded space science and exploration? Some indication is available from the experience of astronauts. Most have said that going to space was a transforming experience, and that they would like to go again. They tend to return to Earth with a more global perspective than when they left. They are more conscious of the fragility of ‘Spaceship Earth'.
When a million and more people visit space each year, we can expect these views to spread, which should make it easier to generate global action to counter the various perils that face our home planet.
There are two historical analogies. First, Europe benefitted greatly from discovering the existence of America. The benefits were both material and cultural. The resulting challenge to traditional thinking provided a boost for the Enlightenment. Could large-scale space exploration and tourism provide a comparable benefit to the entire planet?
Second, many people consider that the main benefit from the Apollo lunar landing programme was the famous Earthrise photograph, Fig. 13.1, of the Earth appearing to rise above the Moon. To quote from a senior NASA Apollo engineer, Henry O Poh, looking back on Apollo: