Propounded by Weizacker in 1944, Kuiper in 1951 and Urey in mid 20th century the ideas were laid down under the general head of Dust-cloud hypotheses. The solar system coagulated from a vast cloud of dust forming the inter stellar matter.
This cloud consisted of dust and diffused gas from which one portion condensed to form the Sun and the others rotating round the Sun eventually formed the planets etc.
The original cloud of dust formed an intricate pattern of turbulent motion. The whole thing was like a spiral nebula which was nothing but a rotating disc of cloudy matter. The nucleus of this disc formed the sun around which there existed a gas-dust envelope. As this envelope revolved around the nucleus (the sun) concentric cells / whirls were formed. In these cells, there were eddies consisting of gas and dust. In course of time, the dusts of each eddy coagulated to form bigger particles and formed what are known as proto-planets.
The gases present in proto-planets were driven away by the pressure of sun’s light. After the complete removal of the gases, the proto-planets gave rise to planets and satellites through contraction of dusts. The bigger concentrations gave birth to the planets and the smaller ones to the satellites.
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This group of hypotheses had acceptance and rejection in close succession.