The Solar System

The Solar System


Introduction

The Solar System consists of the Sun and those celestial objects bound to it by gravity, all of which were formed from the collapse of a giant molercular cloud approximately 4.6 billion years ago. The four smaller inner planets, Mercury, Venus, Earth and Mars, also called the terrestrial planets, are primarily composed of rock and metal.
The four outer planets, the gas giants, are substantially more massive than the terrestrials. The two largest, Jupite and Saturn, are composed mainly of hydrogen and helium; the two outermost planets, Uranus and Neptune, are composed largely of ices, such as water, ammonia and methane, and are often referred to separately as "ice giants".

The principal component of the Solar System is the Sun, that is a star similar to other stars in the night sky. It appears so large and bright to us because it is much closer to Earth. The Sun is composing mostly of hydrogen and helium.

Contents

The objects around the Sun include eight planets:
1. Mercury: is the closest planet to the Sun and the smallest planet in the Solar System. It has no natural satellites, and its only known geological features besides impact craters are lobed ridges or rupes.
2. Venus is close in size to Earth, and like Earth, has a thick silicate mantle around an iron core, a substantial atmosphere and evidence of internal geological activity. It has no natural satellites.
3. Earth: is the largest and densest of the inner planets, the only one known to have current geological activity, and is the only place in the universe where lige is known to exist.
4. Mars: is smaller than Earth and Venus. It possesses an atmosphere of mostly carbon dioxide with a surface pressure of 6.1 millibars. Its surface, peppered with vast volcanoes and rift valleys. Its red colour comes from iron oxide (rust) in its soil. Mars has two tiny natural satellites (Deimos and Phobos).
5. Jupiter, at 318 Earth masses, is 2.5 times the mass of all the other planets put together. It is composed largely of hydrogen and hellium It has 63 Known satellites. The four largest, Ganymede, Callisto, Io and Europa.
6. Saturn, distinguished by its extensive ring system, has several similarities to Jupiter, such as its atmospheric composition and magnetosphere.The rings of Saturn are made up of small ice and rock particles. It has 62 confirmed satellites; two of which, Titan and Enceladus, show signs of geological activity.
7. Uranus, is the lightest of the outer planets. Uniquely among the planets, it orbits the Sun on its side; its axial tiltt is over ninety degrees to the ecliptic. It has a much colder core than the other gas giants, and radiates very little heat into space. It has 27 known satellites, the largest ones being Titania, Oberon, Umbriel, Ariel and Miranda.
8. Neptune: though slightly smaller than Uranus, is more massive (equivalent to 17 Earths). It radiates more internal heat, but not as much as Jupiter or Saturn. It has 13 known satellites.

Conclusion:
Our solar neighborhood is an exciting place. The Solar System is full of planets, moons, asteroids, comets, minor planets, and many other exciting objects.

Our planets Earth is part of the Solar System, and It is unique that have live. Other planets has gas and all is rocks, where the lives is not good.

All eight planets can be seen with a small telescope; or binoculars. And large observatories continue to provide much useful information. But the possibility of getting up close with interplanetary spacecraft has revolutionized planetary science. Very little of this site would have been possible without the space program.