origin of the universe

          All over world are the countless scientific theories that attempt to describe how the universe began.

          The most popular theory on the origin of the universe is the Big Bang theory. It states that at a specific moment in time, some 10-20 million years ago, there was an immense explosion. The explosion sent the particles moving outwards, which then cooled, condensed, and formed the universe, and until this .point of time he universe is still expanding.

          Another theory that explains how the universe came into existence is the solar nebular hypothesis. The idea behind the Solar Nebular Hypothesis is that the solar system was condensed from an enormous cloud of hydrogen, helium, and a few other elements and rocks.   Around five billion years this cloud of materials began to spin and contract together into a disk shape under their own gravitational forces.   The particles started combined together, protoplanets, to eventually form planets.   A great mass of the material eventually began to form together, protosun, and make up the sun. The Solar Nebular Hypothesis makes sense that 
gravitational forces of elements can begin to pull each other in and start spinning in a circle and sense there is less gravity in space that maybe why the planets are still rotating around the sun, which is logically in the center sense it is the largest in mass, even today five billion years later.

          The other theory that tries to explain about the origin of the universe is dust-cloud theory.  According to their dust-cloud theory, the solar system was formed from a slowly rotating cloud of dust and gas that contracted and started to rotate faster in its outer parts, where eddies formed. These eddies were small near the center of the cloud and larger at greater distances from the center. The distances corresponded more or less to the Titius-Bode relation. As the clouds cooled, materials coagulated near the edges of the eddies and eventually formed planets and asteroids, all moving in the same direction. The slowly rotating central part of the cloud condensed and formed the sun, and the sun's central temperature rose as gravity further compressed the material. When nuclear reactions eventually began in the suns interior, about 5 billion years ago, much of the nearby gas was blown away by the pressure of the sun's emitted light. Nevertheless the earthy retained an atmosphere consisting of methane, ammonia, carbon monoxide, water vapor, and nitrogen, with perhaps some hydrogen. In this primitive atmosphere and in the seas below it, organic compounds were formed that eventually resulted in living organisms. The organisms evolved in the next 2 billion years into higher plants and animals, and photosynthesis by plants and the weathering of rock produced the oxygen in the earth's atmosphere.

          These are just some of the theories that try to explain how it began. Even though there are evidences presented to prove their ideas, a lot of questions are still not answered.

Planets on the Solar System

               A planet is a celestial body that revolves around a central star and does not shine by its own light.

            The only planetary system that is known to man is our solar system. It is made up of eight planets. The eight major planets in our solar system are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. There are also many other minor planets, which are also in our solar system, but they are unimportant compared to the eight major planets.Mercury, which is the planet that is closest to the sun, is the first and smallest of the inner planets. It is speculated that the heat from the sun made it impossible for the gases present to become part of the planetary formation. Venus is the second closest planet to the sun and is said to be the most closely resembles to Earth in size, density, and distance from the sun. Most scientists know Venus as the sister planet to the Earth. The only thing different is that Venus is shrouded in thick clouds that completely hide the surface of the planet. The surface temperature is also much warmer than that of Earth. Venus completes one revolution around the sun in 224.7 days. The atmosphere of Venus is made up of 98% carbon dioxide and 2% Nitrogen. This atmosphere also has the presence of helium, neon and argon.

                          Earth is the third planet from the sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four  terrestrial planet. It is sometimes referred to as the world, the Blue Planet The planet is home to millions of speceis, including humans. About 70.8% of the surface is covered by water, with much of the continental shelf below sea level. The submerged surface has mountainous features, including a globe-spanning mid oceanic ridge system, as well as undersea volcanoes,oceanic trenches submarinecanyons,oceanic plateaus and abssayl plains. The remaining 29.2% not covered by water consists of mountains, deserts, plains, plateaus, and other geomorphologies. And the only planet where life exist. Mars is the fourth furthest away from the sun and is recognized by its reddish color. Mars is also very much like the Earth. More than any other planet in the solar system, One thing that is very similar to Earth is the rotation period. Mars rotation period is only thirty-seven minutes longer than the Earth’s. This would explain why Mars has significant seasonal changes just as Earth does. Mars is extremely hard to understand due to the effect of blurring that is caused by the two atmospheres of Mars. It is also known that dust storms are prevalent and leaves the surface of Mars covered by a red haze.Jupiter is the fifth planet and is the most massive of all the planets in this solar system. Its mass represents more than two-thirds of the total mass of all the planets, or 318 times the mass of the Earth Jupiter is surrounded by rings of light which is very prominently visible to earth. The rings are what Jupiter is known for.Saturn is a planet which is also known for its rings and when viewed has a yellow or greyish color. The atmosphere is mostly a clear hydrogen- helium atmosphere. There are also traces of methane, phosphine, ethane, and acetylene. The next planet is Uranus. The atmosphere is made up of mostly methane gas and therefore the planet has a red tint or a bluefish green color. Uranus also has rings but unlike Saturn these rings have almost no small particles.Neptune is the last of the gaseous planets in our solar system. Its atmosphere is much like Uranus’s because it is mostly helium and hydrogen. It also contains methane. Neptune also has rings like its other gaseous partners, but they are very faint.