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Texas ISD School Guide
Texas ISD School Guide







Short Stories for Teachers

The History of the Solar System
By:Helen Klus

When cloud of gas surrounding our newly born, dull yellow, star cooled everything in our solar system was born, the last skin of the dead star, made the same iron that covers the surface of Mars and swims in our blood, all of the material that makes our skin and faces, our hearts and brains were all first made together in a colourful ball of light in the sky. The exploded debris circled the left-over star like water circling a drain, and eventually the lumpiness of the matter meant that it fell together again making different sized spheres at different distances. Some were so heavy that the matter near them began to circle them too, and from this the planets and their moons formed.

The Planets. Far away from the Sun's warmth lies an icy edge to the solar system, the Oort cloud, where one hundred thousand million comets were born. Much further in than this, just outside of the orbit of Neptune, the Kuiper Belt, another cloud of comets, formed from debris of the explosion that were too small to form a planet. The largest of these we call Pluto, five times less massive than our Moon and covered in frozen methane Pluto spins with its twin planet Charon crossing the orbit of Neptune every few hundred years.

The furthest properly formed planet, Neptune, circles forty times closer to the Sun than the first belt of comets. Neptune is full of huge dark blue methane storms and small white clouds. A number of large moons and millions of small ones circle its cold, gaseous body. The small moons make a ring around its centre whilst one of its larger moons, Triton, explodes with volcanic activity producing gases similar to those that used to dominate Earth, possibly even water.

Uranus, the next planet in, is the same deep blue as Neptune and has the same type of ring around it, but it has been knocked sideways from all of the other planets. Its violent past is evident from this, and one of its moons, Miranda, shows deep scars from being blown apart and fused back together again.

Further in still is Saturn, a yellow planet with a million colourful small moons circling around it in hundreds of separate rings. Saturn's outermost moon, Iapetus, is split into two colours, one side is as black as tar and the other as white as snow. It too once had a ring like Saturn's but the rocks fell in making a huge range of mountains across the equator. Another of Saturn's moons, Titan, is shrouded in bright orange clouds which contain within them all the molecules needed to make life. Like Neptune's Triton, Saturn's Titan contains the same materials Earth used to have, but it is cold and its ocean of methane and water is frozen and slushy.

The next planet in is the largest, had Jupiter been any larger it may have lit up to become a star too but it is just a bit too small and is instead a stormy, electronic, red ball of gas, containing a cyclone three times the size of Earth that spins around it at tremendous speeds.

Europa, one of its moons has an ocean of liquid water separating its rocky core and icy surface. In this ocean heat rises like in the underwater volcanoes on Earth, icebergs float above. On another moon, Io, volcanoes explode releasing clouds of sodium above a rocky surface of yellow sulphur. Ganymede is the largest moon in the solar system and is bigger even than Mercury, it is a huge ball of ice and shines like a giant snow ball in the sky.

Jupiter is so large that it pulled apart the planet which was to form next, leaving a scattering of boulders made of iron and semi-precious stones, the asteroids. Asteroids are not massive enough to become spherical, a sphere is formed because everything falls to the centre in the same way that apples fall down to the Earth instead of up to the sky, no matter which side of the world you are on. There is no up and down only the pull of gravity with things always falling towards the heaviest object. Planets and moons are so large that everything falls inwards at the same rate and a sphere is formed, any dents will even out as matter falls in to fill the gap, but the asteroids are too small to pull everything inwards and so are dented and distorted.

Two of these asteroids, Phobos and Deimos were knocked out of their orbit as Mars flew by and now orbit it as moons. The plains of Mars make a sandy desert which was blown by a carbon dioxide wind, just like the Earth used to be. It was warmed by volcanoes, some three times taller than Mt Everest, but like the Earth it is cold at the poles and dry ice snows down.

On the other side of the Earth from Mars lies Venus. Venus is incredibly bright as it is covered in a thick layer of white clouds made from greenhouse gases and gaseous clouds of sulphuric acid. This insulates the planet so that the volcanic and cratered surface exists at the same temperature throughout the day and across its whole surface.

Closest to the Sun lies Mercury, a rocky planet covered with dust, lava flows, and a surface as cratered as the moon.

The Sun. At the centre of the Solar System shines the Sun, a star which orbits the outer half of the galaxy, taking us all with it. At almost five billion years old it is in the middle of its life. In another five billion years it will glow red and expand so far that all of the seas of Earth will boil away, but for now it affects the Earth in far different ways.

Glowing as a fiery ball of hydrogen and helium, its lower atmosphere is made of highly ionised iron and above this ionised oxygen. A magnetic force coils around the Sun, often becoming twisted as it moves faster at the equator than at the poles. When it is strong enough this force cools the surface, darkening it.

Sunspots begin their lives as tiny pores no larger than a granule. They may last just a few hours and disappear, however sometimes they grow as more magnetic fields are brought to the surface. When a pore is over a few thousand kms across it is designated a sun spot. Singular sunspots are often soon accompanied by the appearance of others and a group forms. They usually travel around the sun one to four times, eventually the convection breaks the field up and carries the magnetic field away.

The pressure in the agitated magnetic fields can get so high that it breaks up through the surface. It is so hot here that hydrogen becomes ionised and so negative and positive groups of matter form. At the moment of the explosion a dense cloud of plasma, hotter than the centre of the Sun, is produced. This causes x-ray emission which ionises atoms of iron down to a single electron from 26. Nuclear reactions can create deuterium, but the duration is too short to fuse anything else together. Photons are pushed into the photosphere in a giant flash and one thousand billion tonnes of matter including electrons, ultra violet light and x-rays fly out towards Earth in a solar wind. The acceleration of these particles can reach 100 million, million, million, million Joules. Minutes to hours later a stream of solar cosmic rays, made mostly of protons, reach the Earth, travelling at 99.5% the speed of light. High speed electrons strike the chromospheres simultaneously at up to 1/3 the speed of light.

High energy electrons and ions from the solar flare enter the Earth's magnetosphere, they follow the magnetic field lines striking atoms and molecules in the upper atmosphere, causing them to radiate their emissions, these are the aurora borealis. Aircraft flying near the magnetic poles can get faulty compass reading, pigeons and whales can loose their direction and the x-ray and ultra violet emission can affect the Earth's radio signals.

The number of recorded sunspots fluctuates from day to day as spots pass behind the Sun or as they are born or die, but when the number is averaged over a year a long term cycle becomes clear. Between 1645 and 1715 there were hardly any sunspots, any seen were small and in the southern hemisphere, only rotating once around the Sun, and this minimum corresponded with an unusually cold northern hemisphere.

The Earth and Moon. It took 200 million years for the Earth to fully form into a molten state from a ball of gas and dust. Meteors constantly rained down upon it as the debris of the young solar system settled down. Then, 4.4 billion years ago an object as massive as Mars crashed into the Earth scraping the outside off. This layer broke away and after a year or so fell together again to make the Moon.

As it was flung from the Earth the Moon crashed into hundreds of other tiny rocks which were currently orbiting the Earth. These covered its surface with craters, formed in violent explosions. Rocky rain bombarded the surface boiling some of it away and crushing other pieces into coloured balls of glass, which lay waiting to be picked up by the Apollo crews.

Just as this rain was coming to an end several huge objects hit the Moon's newly formed surface again on the side that faces Earth. They pulled the rocks and white soil up releasing the lava underneath. This swum over the surface, filling the giant craters which create the dark seas.

On the other side of the Moon, facing away from the Earth, the lava was too far below the surface and so it did not rise to cover the mountains. As the Moon solidified the small amount of iron that had been ripped from the centre of the Earth sunk to the bottom. Above the small iron core an outer core of rocks formed, the Moon is full of holes which remain as far down as they can go until they are forced in by gravity. These hole make the Moon ring like a bell when it is struck by meteors and comets as the sound travels straight through the middle.

What was left of the Earth healed, it begun to form an atmosphere of carbon dioxide, nitrogen, methane and sulphur. The Earth is so massive that, unlike the Moon, it held these things in not letting them boil away. The carbon dioxide formed a thick layer above the sky trapping the light of the Sun inside, warming the surface of the Earth so that it did not freeze.

During the next 500 million years the surface was bombarded with comets, which brought with them enough water to fill the dry oceans, and a cocktail of other molecules from which life could grow. Amazingly whatever it was that sparked the creation of life from non-life happened only once in all of the planets history about 4 billion years ago. If we could prove that this happened more than once then it would almost certain that the universe is teeming with life. People are trying to find life forms with alien genetic lines from our own but they do not know where to look, no one can agree on the definition of when non life can be said to become life. Life may have begun as a self replicating mineral, one of the first forms of life could have been a very thin molecular coating which spread from the surface of rock to rock.

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