LauncherOne was a two-stage orbital launch vehicle developed and flown by Virgin Orbit that had operational flights from 2021 to 2023, after being in development from 2007 to 2020. It was an air-launched rocket, designed to carry smallsat payloads of up to into Sun-synchronous orbit (SSO), following air launch from a carrier aircraft at high altitude. The rocket was carried to the upper atmosphere on a modified Boeing 747-400, named Cosmic Girl, and released over ocean. Initial work on the program was done by Virgin Galactic, another Virgin Group subsidiary, before a separate entity — Virgin Orbit — was formed in 2017 to complete development and operate the launch service provider business separately from the passenger-carrying Virgin Galactic business. The first successful flight was on 17 January 2021, which delivered a payload of 10 CubeSats to low Earth orbit (LEO). Three further launches successfully reached orbit. An initial test flight was unsuccessful on 25 May 2020, when the rocket failed to reach space. The final flight on 9 January 2023 also failed to reach orbit. LauncherOne was the first all liquid-fuelled air-launched orbital rocket. From 2007 to 2015, Virgin had intended LauncherOne to be a somewhat smaller vehicle with a payload to low Earth orbit. In 2015, Virgin modified the vehicle design to better target their intended market, and increased the vehicle payload capacity to launched to a Sun-synchronous orbit, suitable for CubeSats and small payloads. Virgin Orbit targeted a launch price around US$12 million for the rocket. With Virgin Orbit shutting down all operations after bankruptcy in 2023, the vehicle is unlikely to see additional launches. Virgin Galactic began working on the LauncherOne concept in 2007, and the technical specifications were first described in some detail in late 2009. The LauncherOne configuration was proposed to be an expendable, two-stage, liquid-fueled rocket air-launched from a White Knight Two carrier aircraft.