"micro-gravity" . . . "spacecraft may not even experience zero G-forces" . "microgravity" . . . . "Microgravity Science" . "micro gravity" . "freeflight" . "Micro-g environment research" . . . "(to good approximation) conditions inside a spacecraft in Earth orbit" . . . "micro-g environment" . . . "microgravity environment" . "microgravity research" . . "Microgravity" . . "gravity at these locations" . "microgravity conditions" . . "Microgravity Environment" . "Micro-g environment" . "microgravity environments" . . . "Microgravity science" . "weightless" . . "Micro-g environment" . "Microgravity research" . .