Simply put, the galaxy is the galaxy in which we live, it contains a cluster of over two hundred billion stars including our Sun and indeed our solar system. It is only one of over one hundred billion galaxies in the observable universe. Our solar system is located on one of the six spiral arms of the Milky Way named Orion, if you are somewhere that has a really dark night sky and are far away from artificial light pollution you can see the Milky Way.

It appears as a hazy band of light forming a large arc that spirals across the sky. It is almost as old as the universe itself, the oldest star found being over thirteen billion years old. The name itself, Milky Way, is a translation from the Greek, Galaxis, which is derived from the word milk, derived from the appearance of spilt milk in the sky. Indeed, the Milky Way was first observed by the Greek philosopher Anaxagoras in the fifth century BCE. Proof of the long debated theory that the Milky Way consisted of a cluster of stars came in 1610 by way of Galileo. In 1755, Immanuel Kant correctly speculated that the Milky Way was a rotating body of a huge number of stars held together by gravitational forces similar to the solar system but on a colossal scale.

And it is a colossal scale - the circumference being between two hundred and fifty and three hundred light years! As big as it is, astronomers are confronted with massive problems when trying to observe it, because the Earth is part of the Milky Way, they can't simply look down on it to study it. So, they explore other galaxies and apply what they learn from viewing them onto the Milky Way.



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There are two possible sources for creating hydrogen. Firstly, it can be created by electrolysis of water, where you split water molecules to create pure hydrogen and pure oxygen. Secondly, it can be created by reforming fossil fuels - oil and natural gas both contain hydrocarbons which are molecules consisting of hydrogen and carbon. Using a device named a fuel processor or reformer you can split the hydrogen from the carbon. However, using this method, you discard the carbon into the atmosphere in the form of carbon dioxide.

This second matter of course does not rid society of it's economic dependency and it continues to destroy the environment. But this is the method that is being touted for fuel cell powered vehicles because petroleum is an easily available hydrogen source until there are hydrogen stations located as widespread as petrol station currently are. But there is no doubt that the first option is the better one, however that option faces a major hurdle. Electrolysis of water requires electricity, we need to figure out how to generate that electricity without using fossil fuels. Of course, there are currently several methods of doing so, including nuclear power, hydroelectric dams, solar cells, wind turbines, geothermal power, wave and tidal power or co-generation (biomass fuels).The problem is that currently these would not provide near enough electricity to create sufficient hydrogen for all the world's needs.

So realistically, we need to increase the amount of electricity produced by these methods most probably concentrating on nuclear and solar power. However, there are problems associated with this as nuclear power has political and environmental issues and solar power provides problems with location and cost. Another issue with putting pure hydrogen vehicles on the road is with the storage and transportation. Hydrogen is a bulky gas and compressed hydrogen contains far less energy than the same volume of petroleum.



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Fossil fuels are running out, there are may different timescales predicted but even by the most optimistic predictions, by the end of this century we will no longer be filling our petrol tanks at our local petrol stations. As the years roll by, we are being all the more pressed into adapting a hydrogen economy. It would be a colossal transformation of our society, in the present climate we depend for almost everything upon fossil fuels.

We heat our homes, places of work, places of leisure; power our transportation; light our cities, towns and villages; communicate across distances; produce clothes, household appliances and methods of transportation with fossil fuels. Indeed, it is hard to think of anything that is not drawn into the net of fossil fuel dependency. In addition, oil is regularly the source of many of the world's problems with wars and fighting breaking out over it's ownership and appropriation. It would indeed be a colossal transformation but it is a transformation that is necessary, some forecast that our resources of crude oil will be exhausted within the next forty years. There are other options to the hydrogen model but they encompass dirtier fossil fuels - coal, tar sand and heavy oil; which are not really valid options as they will only continue to worsen global warming and contribute to the destruction of precious eco-systems.

Hydrogen economy is the way forward - it is the most basic and omnipresent element in the universe, it is renewable, it produces no harmful omissions and its only by-products are heat and pure water. In addition, it can power all of the things listed above that are presently powered by fossil fuels. Amazingly, it would also eradicate our current dependency on oil producing countries because hydrogen can be produced anywhere that you have electricity and water, people can even produce it in their own homes using quite basic technology.



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Basically, a fuel cell converts the chemicals hydrogen and oxygen into water and in the process it produces electricity. It is similar to another electrochemical device with which we are very familiar with - the battery. A battery has all of it's chemicals stored inside and it converts those chemicals into electricity, the battery eventually goes dead and it is necessary to either re-charge it or after awhile it is defunct and needs to be thrown out.

With a fuel cell, the chemicals constantly flow into the cell so it never goes dead. The fuel cell creates a direct current voltage that can be used to power motors and electrical appliances. If the fuel source is not pure hydrogen, then the appliance in which the fuel cell is contained will require a reformer. A reformer transforms hydrocarbon into hydrogen, however they also produce heat and other gases, some of which are harmful to the environment. In addition, the necessity of a reformer will decrease efficiency, with the result that researchers are concentrating on pure hydrogen fuel cell vehicles, despite challenges associated with hydrogen production and storage.

The hydrogen fuel cell is the way of the future but there are still a few hurdles which need to be negotiated. Firstly, the fuel cell is expensive mainly due to the current use of platinum for the metal catalysts, researchers need to seek alternatives to cut down costs. Secondly, the proton exchange membranes need to be made more durable than they currently are to withstand higher and indeed lower temperatures. Thirdly, there must be a comprehensive infrastructure implemented which would include pipelines, truck transport, fuelling stations and hydrogen generating plants.



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