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Демо ЕГЭ 2015 (12-18)
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Space could solve water problems
Have you ever tasted saltwater? I guess you have and if so, you will agreewith me that it’s not very refreshing. In fact, drinking more than a few cups worthcan kill you.
According to the United States Geological Survey, whose mission is tocollect and disseminate reliable, impartial, and timely information that is needed tounderstand the nation’s water resources, about ninety-seven percent of the water onour planet is saltwater; the rest is stored in lakes, rivers, glaciers and aquifersunderground. Moreover, only about one-third of the world’s potential fresh watercan be used for human needs. As pollution increases, the amount of usable waterdecreases.
Water is the most precious and taken-for-granted resource we have on Earth.It is also one of the most threatened resources. Increased population and possibleclimate change will put more and more strain on supplies of this vital resource astime goes on. What could we do in this situation? Though it may seem like sciencefiction, the solution could lie in outer space.
I’m not saying we’re going to be teleporting to a spring on the other side ofthe galaxy or colonizing another planet just to have longer showers – it’s muchmore mundane than that. What we could achieve realistically in this century is thesuccessful use of the solar system’s rare metals and water, barring the invention ofthe matrix.
You may be surprised to learn that the metal in your keys, coins, cell phone,computer, car and everywhere else, originally came to this planet from space.When Earth formed, the heavy metals sank to the center and formed a solid core.The lighter elements formed the mantle and the crust we live on. Asteroids andcomets that struck the Earth brought water and metals to the surface.
There are thousands of asteroids orbiting near Earth. Most asteroids aremade of rock, but some are composed of metal, mostly nickel and iron. Probescould be sent out to these to identify useful ones. Then larger probes could pushthem towards the Earth where they can be handled in orbit.
In order to fuel ships and probes, we simply need to find a source of water,such as a comet or the surface of the moon. We collect the water and pass anelectric current through it from a solar panel. The water separates into oxygen andhydrogen, which in liquid form is a powerful rocket fuel.
Is this really possible? We may soon find out. Private company SpaceX hasalready started delivering equipment to the International Space Station (ISS).The ISS is proof that countries once at each other’s throats, like America andRussia, can work together and pull off multi-billion dollar projects.
Recently, a company called Planetary Resources Inc. made the news forgetting big names like Google and Microsoft to invest in exploring asteroids for material gain. Although it will take many decades, it is wise to put the gears in motion now.
We’ve already landed probes on the surface of asteroids and taken samples from them. We can put something as large as the ISS, which weighs just short of 500 tons, according to National Aeronautics and Space Administration (NASA), in orbit.
We can make a half-million-mile round-trip to get rocks from the moon. We can do all of these things already. They just need to be applied and developed in a smart way.