Its first paying customers are a three-member crew from the Italian Air Force and National Research Council of Italy, with a fourth seat occupied by a Virgin Galactic astronaut instructor. It comes almost two years after Branson soared to the final frontier in a test flight meant to usher in a new era of lucrative space tourism. Thursday's flight includes Colonel Walter Villadei and Lieutenant Colonel Angelo Landolf of the Italian Air Force, Pantaleone Carlucci of the National Research Council of Italy, and Colin Bennett of Virgin Galactic. Virgin Galactic has sold around 800 tickets for future commercial flights -- 600 between 2005 and 2014 for $200,000 to $250,000, and 200 since then for $450,000 each. It competes in the "suborbital" space tourism sector with billionaire Jeff Bezos' company, Blue Origin, which has already sent 32 people into space.