The Unity will be attached to another aircraft when it takes to the skies next month, though: full-powered, independent test flights won't begin until 2017. Virgin Galactic also doesn't have a target date for its first official flight yet despite already having sold 700 tickets. Some of its earliest customers include Lady Gaga, Justin Bieber and Leonardo DiCaprio. Company VP Jonathan Firth told Bloomberg that Virgin Galactic has "thrown out so many dates in the past that [it wasn't] able to keep to," so it's being more conservative this time.