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:
Space tourism fly on Soyuz TMA-14 in March 2009. British-American Richard Garriott became the next space tourist in October 2008 aboard Soyuz TMA-14. As of 2018, Canadian Guy Laliberté is the most recent tourism to fly to the ISS, in September 2009 aboard Soyuz TMA-16. Since the Space Shuttle was retired in 2011, Soyuz once again became the only means of accessing the ISS, and so tourism was once again put on hold. Bigelow Aerospace acquired the designs for inflatable space habitats from NASA's Transhab program, and has already launched two first inflatable habitat modules. The first, named Genesis I, was launched