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  • tallbridge 9:58 pm on November 30, 2009 Permalink |
    Tags: , cosmos, , , , ,   

    Is there an echo in this here cosmos? 

    Dark Power |  Grand Designs for Interstellar Travel | Newscientist 2009

    SPACE is big,” wrote Douglas Adams in his book The Hitchhiker’s Guide to the Galaxy. “You just won’t believe how vastly, hugely, mind-bogglingly big it is.”

    He wasn’t exaggerating. Even our nearest star Proxima Centauri is a staggering 4.2 light years away – more than 200,000 times the distance from the Earth to the sun. Or, if you like, the equivalent of 50 million trips to the moon and back.

    Such vast distances would seem to put the stars far beyond the reach of human explorers. Suppose we had been able to hitch a ride on NASA’s Voyager 1 the fastest interstellar space probe built to date. Voyager 1 is now heading out of the solar system at about 17 kilometres per second. At this rate it would take 74,000 years to reach Proxima Centauri – safe to say we wouldn’t be around to enjoy the view.

    So what would it take for humans to reach the stars within a lifetime? For a start, we would need a spacecraft that can rush through the cosmos at close to the speed of light. There has been no shortage of proposals: vehicles propelled by repeated blasts from hydrogen bombs, or from the annihilation of matter and antimatter. Others resemble vast sailing ships with giant reflective sails, pushed along by laser beams.

    All these ambitious schemes have their shortcomings and it is doubtful they could really go the distance. Now there are two radical new possibilities on the table that might just enable us – or rather our distant descendants – to reach the stars.

    In August, physicist Jia Liu at New York University outlined his design for a spacecraft powered by dark matter (arxiv.org/abs/0908.1429v1). Soon afterwards, mathematicians Louis Crane and Shawn Westmoreland at Kansas State University in Manhattan proposed plans for a craft powered by an artificial black hole (arxiv.org/abs/0908.1803).

    No one disputes that building a ship powered by black holes or dark matter would be a formidable task. Yet remarkably there seems to be nothing in our present understanding of physics to prevent us from making either of them. What’s more, Crane believes that feasibility studies like his touch on questions in cosmology that other research hasn’t considered.

    Fuel as-you-go

    Take Liu’s dark matter starship. Most astronomers are convinced of the existence of dark matter because of the way its gravity tugs on the stars and galaxies we see with our telescopes. Such observations suggest that dark matter outweighs the universe’s visible matter by a factor of about six – so a dark matter starship could have a plentiful supply of fuel.

    Liu was inspired by an audacious spacecraft proposed by the American physicist Robert Bussard in 1960. Bussard’s “ramjet” design used magnetic fields generated by the craft to scoop up the tenuous gas of interstellar space. Instead of using conventional rockets, the craft would be propelled by forcing the hydrogen gas it collected to undergo nuclear fusion and ejecting the energetic by-products to provide thrust.

    Because dark matter is so abundant throughout the universe, Liu envisages a rocket that need not carry its own fuel. This immediately overcomes one of the drawbacks of many other proposed starships, whose huge fuel supply greatly adds to their weight and hampers their ability to accelerate. “A dark matter rocket would pick up its fuel en route,” says Liu.

    Read On..

     
  • untamedyawp 4:15 am on July 23, 2009 Permalink |
    Tags: , , bill hicks, , , cosmos, , david icke, holographic reality, , , orwell, oxford, reality,   

    david icke 

     
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