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nebular hypothesis

American  

noun

Astronomy.
  1. the theory that the solar system evolved from a mass of nebular matter: prominent in the 19th century following its precise formulation by Laplace.


nebular hypothesis British  

noun

  1. the theory that the solar system evolved from the gravitational collapse of nebular matter

"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

nebular hypothesis Scientific  
/ nĕbyə-lər /
  1. A model of star and planet formation in which a nebula contracts under the force of gravity, eventually flattening into a spinning disk with a central bulge. A protostar forms at the nebula's center. As matter condenses around the protostar in the bulge, planets are formed from the spinning matter in the disk. This theory is widely accepted to account for the formation of stars and planetary systems such as ours. The first version of the nebular hypothesis was proposed in 1755 by the German philosopher Immanuel Kant and modified in 1796 by Pierre Laplace.

  2. ◆ The nebula that according to this hypothesis condensed to form the solar system is called the solar nebula.


Etymology

Origin of nebular hypothesis

First recorded in 1830–40