Nebular Hypothesis Of Laplace
French Mathematician Laplace propounded his Nebular Hypothesis in the year 1796. Laplace’s hypothesis is just the modified version of Kant’s hypothesis. Laplace propounded his hypothesis without mathematical formulation. In fact, Laplace postulated his hypothesis after removing the inherent weak points and erroneous concepts of Kant’s hypothesis which suffered from three basic defects e.g.
Assumptions of Laplace’s Hypothesis:
The Origin Of The Earth According To Laplace:
Based on aforesaid assumptions Laplace maintained that there was a hot and rotating huge gaseous Nebula in the space.There was gradual loss of heat from the outer surface of the Nebula through radiation due to circular motion or rotation of the Nebula. Thus, gradual loss of heat resulted into the cooling caused gradual concentration in the size of the Nebula. Thus, reduction in the size and volume of the Nebula increased the circular velocity of the Nebula. As the size of the Nebula continued to decrease, the velocity of rotatory motion continued to increase. Thus, the Nebula started spinning at very fast speed and consequently the centrifugal force became so great that it exceeded the centripetal force. When this stage was reached the materials at the equator of the Nebula became weightless. Consequently, the outer layer was condensed due to excessive cooling and so it could not rotate with the still cooling and contracting central nucleus of the Nebula and thus the outer ring was separated from the Nebula and it started moving around the Nebula. This original ring was divided into nine rings and each ring moved away from the other ring. All the materials of each ring condensed at a point or knot in the form of ‘hot gaseous agglomeration’. Each such agglomeration was later on cooled and condensed to form planet. Thus, nine planets were formed from nine rings and the remaining central nucleus of the Nebula became the sun. Satellites were formed from the planets due to repetition of the aforesaid mechanism and processes.
- K.Siddhartha – “The Earth’s Dynamic Surface”
- S.Singh – Geomorphology
- Strahler & Strahler – Physical Geography
- M.J.Shelby – Earth’s Changing Surface
Read about Knat’s Hypothesis,