 This flight project was eventually discontinued, but a number of ground studies were conducted.The research has given rise to several very useful offshoots, including the ground-based Vestibular Research Facility located at ARC.OFO should not to be confused with similar acronyms describing the Orbiting Observatory series of spacecraft, such as Orbiting Geophysical Observatory (OGO), Orbiting Solar Observatory (OSO), and Orbiting Astronomical Observatory (OAO).