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In astrophysics, spaghettification (sometimes referred to as the noodle effect〔 〕) is the vertical stretching and horizontal compression of objects into long thin shapes (rather like spaghetti) in a very strong non-homogeneous gravitational field; it is caused by extreme tidal forces. In the most extreme cases, near black holes, the stretching is so powerful that no object can withstand it, no matter how strong its components. Within a small region the horizontal compression balances the vertical stretching so that small objects being spaghettified experience no net change in volume. Stephen Hawking describes the flight of a fictional astronaut who, passing within a black hole's event horizon, is "stretched like spaghetti" by the gravitational gradient (difference in strength) from head to toe. However, the term "spaghettification" was established well before this.〔For example, , a companion to a one-off BBC TV documentary: ''The Key to the Universe''.〕 ==A simple example== center The four objects follow the lines of the gravitoelectric field,〔Thorne, Kip S. ♦ (Gravitomagnetism, Jets in Quasars, and the Stanford Gyroscope Experiment ) From the book "Near Zero: New Frontiers of Physics" (eds. J. D. Fairbank, B. S. Deaver, Jr., C. W. F. Everitt, P. F. Michelson), W. H. Freeman and Company, New York, 1988, pp. 3, 4 (575, 576) ♦ ''"From our electrodynamical experience we can infer immediately that any rotating spherical body (e.g., the sun or the earth) will be surrounded by a radial gravitoelectric (Newtonian) field ''g'' and a dipolar gravitomagnetic field ''H''. The gravitoelectric monopole moment is the body's mass M; the gravitomagnetic dipole moment is its spin angular momentum S."''〕 directed towards the celestial body's centre. In accordance with the inverse-square law, the lowest of the four objects experiences the biggest gravitational acceleration, so that the whole formation becomes stretched into a filament. Now imagine that the green blobs in the diagram are parts of a larger object. A rigid object will resist distortion—internal elastic forces develop as the body distorts to balance the tidal forces, so attaining mechanical equilibrium. If the tidal forces are too large, the body may yield and flow plastically before the tidal forces can be balanced, or fracture. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「spaghettification」の詳細全文を読む スポンサード リンク
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