The Theory of Acreción Panetaria Is the hypothesis proposed by the geophysicist and Soviet astronomer Otto Schmidt on the formation of stars, planets, galaxies, asteroids and comets in 1944.
Accreditation is the process by which the mass of a body is increased by the accumulation of matter, both in the form of gas and small solid bodies that collide and adhere to the body (Ridpath, 1998, p.10).
In other words, the planets slowly formed over millions of years as a result of particles of gas and dust clouds from planetary nebulae that were adhered to rocky bodies, forming an accretion disk.
The addition of the one to the other is not a harmonious but rather violent process as the gravitational force of the larger matter accelerates the speed at which smaller rockets (or stellar dust) are attracted and producing a strong impact.
It is believed that the stars, planets and satellites of the Solar System, including galaxies, were formed in this way (Ridpath, 1998, p.10). Some stars are still formed by an accretion disk.
This theory, although relatively new, maintains precepts of models and theories of greater date; Beginning with the Nebular Theory of Descartes in 1644 and best developed by Kant and Laplace in 1796.
Articulation of planetary accretion theory
The Planetary Accreditation Theory Is based on the heliocentric model which holds that the planets orbit the Sun. This heliocentric model was first proposed by Aristarchus of Samos (280 BC) but its postulate was not very considered and the idea of Aristotle Of the unfixed Earth orbiting the Sun at the center of sidereal space (Luque, et al., 2009, p.130), which governed for 2000 years.
The Renaissance Nicolas de Cusa dusted off the ideas of Aristarchus of Samos, without any acceptance in the scientific community of the time.
Finally, Nicolaus Copernicus Proposed the idea of a planetary system revolving around the Sun Which was reluctantly accepted in principle and subsequently backed by Galileo Y Kepler .
Curiously, the problem of the origin of the planets and the Sun was not considered by science until long after the Copernican revolution (Luque, et al., 2009, p.
Descartes , At the beginning of the 17th century proposes Nebular Theory In which he affirms that the planetary bodies and the Sun formed simultaneously from a cloud of stellar dust.
In the 18th century, with the Contributions by Newton On the mechanics in which he studied the movement and solid particles in the elliptical direction paved the way for Emanuel Swedenborg in 1721 to propose the Nebular Hypothesis as an explanation of the creation of the Solar System.
Swedenborg was convinced that this was formed by a great nebula whose matter would concentrate to form the Sun first and that around it rotational gravitation rotating at high speed stellar dust that was condensing and forming the planets.
In 1775, Kant, a connoisseur of Swedenborg's theory, proposed the idea of a primitive nebula from which the Sun and its system of planets emerged (Luque, et al., 2009).
Laplace's Pierre Simon polishes analytically by concluding that the nebula contracted under the influence of its own gravitation and its rotational speed increased until it collapsed on a disk. Later gas rings were formed that were condensed in planets (Luque, et al., 2009).
At the end of the 19th century some objections to the theory began to emerge. One of them was proposed by James Clerk Maxwell who differed of the idea of Laplace on a ring of planetoides that accreted the planets.
Our Solar System began to form 4658 million years ago and the planets about 4550 million years ago (Luque, et al., 2009, 152). The first celestial body that was formed is the Sun, the unique and central star of the Solar System.
Star accent
After a supernova explosion, gas clouds and stellar dust expand and their shock wave can cause the collapse of a nearby giant molecular cloud.
If the density of the cloud increases so much that the gravitational force exceeds the tendency of the gas to expand (Jakosky, 1998, p 247).
Minor clouds can form from the larger cloud which will continue a gradual and independent process of contraction to form one or several stars.
In the case of our Solar System, stellar matter was concentrated in the center and this increased the pressure, which released energy and formed a proto-star almost 5000 million years ago that would later become the Sun. (Ridpath, 1998, p. 589).
Initially, in the embryonic state, the Protosol Had less mass than the Sun has today (Ridpath, 1998, page 589).
Accretion of planets
A nebula laden with hot disc-shaped gases, revolves around its axis. When the gas loses energy by radiation, it begins to contract and increases its speed of rotation to conserve its angular momentum.
At a certain point in this contraction process, the velocity of the outermost ring of the disc was sufficient for the"centrifugal force"to be greater than the gravitational pull toward the center (Gass, Smith, & Wilson 1980: 57) . From this ring, called Acretion Disc , The planets arose.
The Accuracy Discs Are the rings of matter that gravitate around a compact object by attracting the atmosphere of another nearby star (Martinez Troya, 2008, p.
Among the variety of gases, substances and stellar material that revolves around a compatacto object are the Planetesimals .
The Planetesimals Are rocky bodies and / or helium of 0.1 -100 km in diameter (Ridpath, 1998, p 568). The accretion of several planetesimals, successive colossal clashes of rocks of different sizes; Gradually formed the protoplanets or planetary embryos that long afterwards gave way to the planets (major or minor).
Comets are thought to be icy planetesimal remnants of the formation of outer planets (Ridpath, 1998, p.145).
References
- Gass, I.G., Smith, P.J., & Wilson, R.C. (1980). Chapter 3. The Composition of the Earth. In I. G. Gass, P. J. Smith, & R. C. Wilson, Introduction to the Earth Sciences (pp. 45-62). Seville: I reversed.
- Jakosky, B. (1998). 14. Formation of planets around other stars. In B. Jakosky, The Quest for Life on Other Planets (pp. 242-258). Cambridge: Cambridge University Press.
- Luque, B., Ballesteros, F., Márquez, Á., González, M., Agea, A., & Lara, L. (2009). Chapter 6. Origin of the Solar System. In B. Luque, F. Ballesteros, Á. Márquez, M. González, A. Agea, & L. Lara, Astrobiology. A bridge between the Big Ban and life. (Pp. 129-150). Cambridge: Cambridge University Press.
- Martínez Troya, D. (2008). Acretion Disc. In D. Martínez Troya, The Stellar Evolution (pp. 141-154). BooksEnRed.
- Ridpath, I. (1998). Accretion. In I. Ridpath, Dictionary of Astronomy (pp. 10-11). Madrid: Editorial Complutense.
- Trigo i Rodríguez, J.M. (2001). Chapter 3. The formation of the Solar System. In J. M. Trigo i Rodríguez, The Origin of the Solar System (pp. 75-95). Madrid: Complutense.