a condition, especially in space orbit, where the force of gravity is so weak that weightlessness results.
Origin of microgravity
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
the very low apparent gravity experienced in a spacecraft in earth orbit
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
A condition in which an object in the gravitational field of some other body (such as the Earth) is accelerated freely as a result of the gravitational force. Free-falling objects, such as a skydiver or a satellite orbiting the Earth, are in a condition of microgravity, while objects held up by forces resisting gravity (as in the case of objects resting on the Earth's surface) or held up by aerodynamic forces (as in the case of birds or aircraft) are not. Since the normal experience of weight on Earth is the result of forces that resist gravity, objects in microgravity appear weightless. Not all effects of gravity are eliminated in such conditions; tidal forces, for example, still affect bodies in microgravity, especially large bodies such as the Earth and the Moon.
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