The condition of near weightlessness induced by free-fall or unpowered space flight. It also refers to the scientific discipline concerned with the evaluation of the processes in a near-zero gravity environment, particularly those of fluid physics, life, and material sciences. Search for microgravity books on Amazon.co.uk
Condition of near-weightlessness experienced by a person or object in free fall as it orbits a star or planet. In a spacecraft orbiting the Earth, gravity is reduced to one ten-thousandth (1/10000) of its value at the planet's surface.