Learn more about how the Solar System was built

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Learn more about how the Solar System was built


After the Big Bang, it took the Universe a billion years to evolve into an elaborate tapestry of galaxies and stars. Over the next 12 or so billion years, more stars and galaxies gradually weaved themselves into existence, reincarnated from the dying embers of elderly predecessors.
Our Solar System is a relative newcomer in this lengthy tale of cosmic creation. A drifting gas cloud on the very edge of the Milky Way slowly began to shrink and spin round. This cloud, or nebula, gradually contracted to a disc about the size of Neptune's orbit, and as it did so it heated up. Once the nebula had warmed to a few thousand degrees, it began to separate into two different clouds. The scorching centre continued heating until eventually the Sun exploded into action about 5 billion years ago. The rest levelled out to form a revolving disc that gradually cooled down.
As the temperature dropped, the gas quickly condensed into tiny solid particles of rock, metal and ice. As they smashed into each other inside the spinning disc they stuck together to form pebbles. These pebbles rapidly fused to form rocks, then boulders and eventually, after around 100 million years, a set of nine complete planets in stable orbits.


The characteristics of each of the planets also reflect their position in this cosmic cooking pot. Around the inner region near the scorching Sun the planets are made from toughened rock and metal, because all the lumps of ice were vaporized and blown away. Later, as the solar system cooled, these ejected gases condensed and clung back onto the surface of a few of the farther planets, such as our Earth.
The cooler outer planets managed to keep hold of more of this vapour, which clung to their rocky cores, forming the gas giants like Jupiter and Saturn. Right out at the barren edge of the Solar System, as it gradually merges into the freezing void of space, the icy remnants congregated. It is here that the comets reside, the frozen balls of ice and rock that light up as they swing past the Sun on their grand orbits.

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STARS

Our Sun is just one of an estimated 100 billion billion stars in the Universe. Delve into the dramatic lives of these dazzling fireballs with our guide to the stars.[/SIZE]

Birth


The Hubble telescope has sent back some beautiful images of nebulae - stunning spacescapes filled with bright gas clouds that stretch for millions of miles. These areas are the stellar nurseries of space - from deep inside these placid panoramas, stars explode into life. Learn how stars are made in Birth.

Death


In Death you can learn about the cataclysmic events that herald the end of a star's life. Whether shrinking to become a white dwarf or imploding to form a black hole, the death of a star is a dramatic spectacle.

Star Types


From exploding supernovae as bright as a whole galaxy, to supersonic pulsars spinning hundreds of times a second, there's a cosmic zoo of stars out there. Explore the the stellar neighbourhood with Star Types.

Inside Stars



All the chemicals in your body, from the calcium in your bones to the zinc in your hair, were originally forged in the fiery furnaces inside stars. Over the past 12 billion years, these chemicals have passed through the cores of at least two stars before settling inside you. Learn more about cosmic recycling in Stellar Soup

Why Stars Twinkle


Starlight can take billions of years to filter down to Earth from the furthest reaches of the Universe. With it arrives a plethora of information about the star's size, weight, chemical composition and age. Find out why a star's twinkle holds the clue to its cosmic character.
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I hope these information are useful for all whom interested in this subject .