SOLAR PLANETS

Solar Planets

Earth is one planet in the solar system, and there is The universe within an infinite amount. As we know that in the universe there is not only one our solar system alone but still there is more to thousands in number, until now no one knows for sure. There are new allegations based on the observation of the earth and from space.

Solar or solar system is a system consisting of the sun and the planets and celestial bodies that revolve around it, according to a specific orbit. The planets can remain in orbit due to gravitational pull.

The formation of our solar system similar to the sun the other in the universe. Regarding the formation of the solar system there are several theories, one of which is the theory or model Nobular; in the universe that seems hollow, actually contain the atoms of various elements, which is spread everywhere in the form of "cloud" thin, thin gaseous turbulent and rotating. When a thin gas clouds are slowly solidified by grouping scattered atoms, was born the solar center of the sun. The kinetic energy of the rotating gases and volatile increases the rotation of the sun and its planets.

Groups the atoms caused by the force of gravity and because the movement of the atoms are moving slowly toward each other, making the gas becomes hotter and more dense. One of the processes, group this gas formed the earth and other planets, Figure 1.1 shows the nebular theory of this process.

More than 99 percent of the atoms in space is hydrogen and helium are the two lightest atoms. Near the center of the cloud of gas, the atoms are in a high pressure and temperature so that hydrogen and helium begin to merge, to form heavier elements. Merger of lighter elements into heavier elements causing the release of heat energy. Hydrogen and helium nuclear burning experience.

The sun is formed when the nuclear burning begins in a cloud of gas, approximately 6,000 million years ago. Limited the nuclear burning of gas clouds in the center. While the low-pressure gas is still spinning rapidly around its center, the sun.

Turnover create centrifugal force, pulling towards the outside, whereas gravity tends to pull the gases inside, towards the sun. As a result of these two opposing forces is slowly making a flat-shaped cloud of gas, forming a disc of gas rotating around the sun, and called nebulae planetaria.

The outside of the cooler nebular planetaria, become quite dense and allow condensed solid materials. Which eventually became the planets, Figure 1.2.

Another theory about the formation of the solar system proposed by experts in cosmology (cosmologist), as a "big bang", which occurs in 20 billiun (10 9) years ago. According to this theory, at some point the entire universe together into a solid sphere,

FIGURE 1.1. Solar system formation model Nobular. Solar system starting from a rotating cloud of gas (A). Most of the mass is concentrated in the center and formed the Sun, and the rest of the material accumulated to form planets concentrated (B). The solar system today (C). Earth is the third planet from the Sun, about 150 million kilometers and has a unique composition that allows the existence of life. (Carla W Montgomery, 1989) 

hot and very massive. Then there was a massive explosion destroyed it and produce splinters thrown to everywhere rotating direction and form the solar system-solar. Celestial bodies that formed this move away from each other. And one day the motion is slow and the system will stop. Then the force of gravity will put it back together, maybe 20 billion years later, became a "ball of fire" again. Furthermore happen again 'big-bang' which in the instant form the solar system-solar new.

Today we know the sun as the center of the solar system, surrounded by the planets, including planet Earth, orbiting around it, or heliocentric. Ellipse-shaped orbit trajectory. However, at the time BC was not the case. Yunani who had studied astronomy, believes will geocenric, which means the earth was the center of the solar system. The sun and stars moving around the earth. At that time believed that the earth is round (spheric), not moving or stationary, and surrounded by a transparent space where the stars hung.

In the solar system we know today, the sun surrounded by nine planets, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. Based on the mass density and distance from the sun, grouped into Terrestrial Planets, which is the fourth planet nearest the sun and the other Jovian planets.

Terrestrial planets, Mercury, Venus, Earth and Mars, are similar to the Earth, has a large mass meeting, 3 g / cm 3 or more and small. While the Jovian planets, Jupiter, Saturn, Uranus, Neptune and Pluto, similar to Jupiter, the path farther from the Sun, its mass is smaller meetings, only 0.7 to 1.3 g / cm 3, but its mass is much greater . For example Jupiter and Saturn, has a mass of 317 and 95 times the mass of the earth, so the shape is larger than the Earth.

The planets nearest the sun at high temperature, composed of materials that can only be condensed at high temperatures, such as iron (Fe), silicon (Si), magnesium (Mg) and aluminium (Al). The planets that are far from the sun's temperature is lower and consists of such elements in addition to the above, as well as volatile elements, such as hydrogen, helium and sulfur gases that can form even at low temperatures.

Figure 1.2 Composition of the solar system. Jovian planets much larger than the Terrestrial planets. The sun is the center and a few hundred times larger than planets, (Skinner, 2004).