Liquid Liquid A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. As such, it is one of the four fundamental states of matter (the others being solid, gas, and plasma), and is the only state with a definite volume but no fixed shape. A liquid is made up of tiny vibrating particles of matter, such as atoms, held together by intermolecular bonds. Water is, by far, the most common liquid on Earth. Like a gas, a liquid is able to flow and take the shape of
History of Solar System formation and evolution hypotheses a solution to the angular momentum problem and does not explain lunar formation nor other very basic characteristics of the Solar System. The Weizsäcker model was modified in 1948 by Dutch theoretical physicist Dirk Ter Haar, in that regular eddies were discarded and replaced by random turbulence which would lead to a very thick nebula where gravitational instability would not occur. He concluded the planets must have formed by accretion and explained the compositional difference (solid and liquid planets) as due to the temperature difference between the inner and outer regions, the former being hotter and the latter being cooler,