WHAT IS THE NEBULAR THEORY? - SCIENCE - 2025

The nebular theory is a scientific explanation of the formation of planets. It was formulated for the first time in the 17th century by Descartes, and later developed and modified by other thinkers such as Kant, Laplace or Swedenborg.

When Descartes first raised it, he was trying to explain that the planets were created at the same time from a cloud of stellar dust.

Later, this initial approach was investigated and developed by other scientists and humanists. Over the centuries, different theories have emerged around that of Descartes, so that the study of the origin of the planets is extensive.

Thus, in addition to Kant, Laplace and Swedenberg, already in the 20th century other physicists such as Emil Belot or Lyman Spitzer delved into the nebular theory updating the existing postulates.

Descartes' nebular theory

In 1644, Rene Descartes proposed that the creation of the Sun and the planets had occurred from a cloud of stellar dust. These clouds of star dust in the universe are also called nebulae.

Nebulae are made up of gases and chemical elements. The most common gases are helium and hydrogen, while the chemical elements are in the form of cosmic dust.

According to Descartes, this nebula evolved in such a way that the Sun arose in the center. Later, by collision of the other fragments detached from this phenomenon, the planets around the Sun appeared.

The theories of Kant and Laplace

In the 18th century, Kant and Laplace developed Descartes' original theory and reasoned that the original nebula had undergone a very large cooling. Later, due to gravitational forces, it contracted forming a flat disk with a very fast rotation.

Thus, as the center of the disk grew larger, the Sun arose. Later, the other planets were created by centrifugal forces.

Birkeland's theory of electromagnetic forces

At the end of the 19th century, the Norwegian physicist Kristian Birkeland formulated another theory, according to which the electromagnetic forces of the Sun were those that were strong enough to create the planets.

That is, these electromagnetic forces would have caused the condensations necessary to create the planets by gravity.

Emil Belot and centripetal and centrifugal forces

At the beginning of the 20th century, Emil Belot proposed a new theory according to which the planets would have been created from solar movements. These, by generating centripetal and centrifugal forces, would have caused instability in the primitive nebula.

From there, the planets formed, according to Belot, on the crests of the waves generated by the vibration of the nebula.

Next to Belot's theory is Otto Yulievich's Accretion Theory, who claimed that the Sun was a star that had trapped a large amount of interstellar dust. Then, from the Sun's own movements, the planets would have arisen.

More modern theories

As we have seen, since the initial postulates of Descartes, there have been many changes and variants introduced by other scientists and thinkers.

Some of the more recent ones, such as Lyman Spitzer's, suggest that matter was put under pressure by radiation from neighboring stars.

Thus, a grouping of matter was created in some regions, triggering the mechanism of creation by accretion.

These theories are constantly revised and renewed, although the original approach of Descartes, and the subsequent updates of Kant and Laplace continue to be taken as a reference in the field of physics and astronomy when studying the origin of the planets.

References

1. "Nebular Hypothesis", Bradley Hoge. (2016).
2. "The Nebular Hypothesis", Herbert Spencer. (1888).
3. "Suborganic Evolution or Thoughts on the Nebular Hypothesis", Albert Leverett Gridley. (1902).
4. Kant-Laplace nebular hypothesis, on Encyplaedia Britannica, at britannica.com.
5. A Brief History and Philosophy of Physics, by Alan J. Slavin on Trent University, at trentu.ca.