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gravitational wave - n. a distortion or movement like a ripple in the space, caused by violent and energetic processes in the Universe.
ripple – n. a small wave or series of waves
black hole - n. in space, an object with so much mass, nothing, not even light can escape its gravity.
ripple in the fabric of space-time – phrase: wave moving through space
atom –n. the smallest particle of a substance that can exist by itself or be combined with other atoms to form a molecule
galaxy –n. any one of the very large group of stars that make up our universe
bell - n. a hollow object, typically made of metal, that sounds a clear musical note when struck
