The universe is a huge place and people exist in a small part of it. The area human beings, animals, and other creatures occupy is what is referred to as the Solar System. It comprises formations which we recognize as planets, satellites that orbit these planets, and an average-sized star that we identify as the Sun. The four inner planets of the solar system are known as ‘Terrestrial Planets.’ This is because their major components are metals and silicate rocks. The other four planets are identified as ‘Jovian’ planets. Also, you can refer to them as ‘gas giants.’
When did it form?
The formation of the solar system took place back in ancient history. It came as a result of the gravitational collapse of the area within a huge molecular cloud which consists of stellar dust. This molecular cloud was a part of what we identify as a nebula. At a particular point, this molecular cloud distorted into itself. The hydrogen atoms in the nebula started fusing into helium thereby emitting an incredible amount of energy in the form of a material disk. The solar system formation is responsible for the birth of the sun.
The other leftover (one percent) material was not consumed by the sun. It started fusing because of gravity as it was propelled outwards. A collision of big objects took place thereby forming larger objects which took the form or shape of spheres. These spheres are what we nowadays refer to as planets and dwarf planets. The formation of terrestrial planets took place near the sun. This is because these icy and gaseous planets are unable to survive near a lot of heat. Gas and icy patterns or structures formed further away. This created gas and ice giants.
The solar system comprises asteroids. These asteroids are bits and pieces which never took the structure of planets. Comets are far out. There has been no modifications or changes in their composition since the formation or creation of the solar system.
Solar System formation and evolution hypotheses
For many centuries human beings have been wondering how the universe came to existence. Some have been searching for articles from the best essay writing service. But, within the past few decades, the predominant theories, thanks to the Scientific Revolution have been pragmatic in nature. During this period, physicists and astronomers started formulating evidence-based descriptions on how the Sun, planets, and universe came to be.
When it comes to solar system formation, scientists often use the Nebular Hypothesis. This theory suggests that the sun, planets, and other objects were formed from nebulous material. Before the solar system formation, the sun and the planets were a giant molecular cloud of gas and dust. But, there was a gravitational collapse that contributed to the solar system.
What about the sun?
The sun is the most massive component of the solar system. As per the sun history, it is known as the star of the solar system. It emits densities and temperatures in its core. These are sufficient to maintain a nuclear mixture of hydrogen into helium thereby making it a primary-sequence star. An enormous amount of energy is released. It is then radiated in space thus peaking in visible light.
The temperature of the sun is intermediate between that of the coolest and hottest stars. Stars that are hotter and brighter than the sun are rare. Those which are cool and dimmer (red dwarfs) cover 85 percent of stars found in the Milky Way. Also, the sun has a greater abundance of elements which are heftier than helium and hydrogen. These dense elements were within the cores of prehistoric and exploding stars. Thus, first-generation stars had to be extinct before atoms enriched the universe. Old stars had few metals while those born later have more. It is presumed that the high metallicity is fundamental to the development of the sun’s planetary system.
A significant percentage of the solar system comprises the interplanetary medium. Together with light, the sun exudes solar wind (incessant stream of charged particles). This solar wind spreads outwards creating a fragile atmosphere that infiltrates the interplanetary medium out. Activities on the sun’s surface, for instance, solar flares intrude the heliosphere hence building space weather. It also causes geomagnetic storms.
The nebular theory faces an impediment of angular momentum. Thus, alternative theories have been used to elucidate more on the formation of the solar system. Some of them include:
- Tidal theory: The formation of planets is because of the approach of another star to the sun.
- Kuiper’s theory: The solar nebular can be co-genetic with the sun because of the prospective occurrence of gravitational instabilities in the solar nebula. The distribution of density would determine the formation of the planetary system.
- Capture theory: The formation of the solar system is from tidal collaborations between a low-density protostar and the sun. The gravity of the sun would draw material from the protostar’s diffuse atmosphere. It would then collapse thereby forming the planets.
There was negation of these hypotheses in the late 1960s. Apollo missions introduced new scientific proof. This explained more about the composition of the moon, its age, and its history. This proof contradicts most predictions by earlier theories. It suggests that rocks from the moon had a noticeable decrease in water comparative to the solar system’s rocks. Additionally, the isotopes of oxygen in lunar rocks exhibit a perceptible resemblance to those on earth.
White dwarfs and Red giants
The evolution hypotheses have been used to try and isolate the sun’s physical source of energy. This led to the discovery of white dwarfs and red giants. White dwarfs are stars that comprise a bright primary sequence star. They are very dense. Red giants are stars which have a solar mass that has little or no hydrogen in their cores. They also resorted to scorching the hydrogen which was fund in their outer shells. Thus, they are believed to be stars that are in the final stages of their lifecycle.
In conclusion, for many centuries, people have been wondering how the sun, planets, and other objects came into existence. Many theories have been used to discuss much about it. Some have not been concise thus alternative theories were used. Also, in the search for clear theories to describe the formation of the solar system, other discoveries were made such as the solar wind (interplanetary medium).