Space architecture of space and a space transportation infrastructure can be accelerated. Virgin Galactic has indicated plans for an orbital craft, SpaceShipThree. The demand for space tourism is one without bound. It is not difficult to imagine lunar parks or cruises by Venus. Another impetus to become a spacefaring species is planetary defense. The classic space mission is the Earth-colliding asteroid interception mission. Using nuclear detonations to split or deflect the asteroid is risky at best. Such a tactic could actually make the problem worse by increasing the amount of asteroid fragments that do end up hitting the Earth. Robert Zubrin writes:
Business tourism those numbers for UK may be closer to 30%. Sharma (2004) cited a UNWTO estimated that business tourism accounts for 30% of international tourism, through its importance varies significantly between different countries. Compared to regular tourism, business tourism involves a smaller section of the population, with different motivations, and additional freedom-of-choice-limiting constraints imposed through the business aspects. Destinations of business tourism are much more likely to be areas significantly developed for business purposes (cities, industrial regions, etc.). An average business tourist is more wealthy than an average leisure tourist, and is expected to spend more money. Business tourism can be