Not to be wholly outdone, Virgin Galactic's suborbital spaceship-for-tourists, seen here being carried by its mothership WhiteKnightTwo, is expected to finish testing over the course of the year. The two-vehicle package will take off from a runway at Spaceport America and climb to an altitude of about 50,000 feet. The mothership will then release SpaceShipTwo, and the ship's engines will kick in to send it throttling into space. The launch sequence is reminiscent of the X-15, the first winged aircraft to achieve sub-orbital flight.

A ticket will set you back $200,000 (but the company only requires a $20,000 deposit). Virgin Galactic refuses to set a date for when it will begin flying its paying customers to the edge of space, but some are hoping to see flights start as early as the end of 2011.

In addition to what it means symbolically, the rise of private spaceflight will be particularly important, because...