Newton knew what he had done. He was no accidental writer. A parabola, of course, is a curve that keeps on going – and that meant that at the end of a very long and very dense book, he lifted off again from the hard ground of daily reality and said, in effect, look: All this math and all these physical ideas govern everything we can see, out to and past the point where we can’t see anymore.
Most important, he did so with implacable rigor, a demonstration that, he argued, should leave no room for dissent. He wrote “The theory that corresponds exactly to so nonuniform a motion through the greatest part of the heavens, and that observes the same laws as the theory of the planets and that agrees exactly with exact astronomical observations cannot fail to be true.” (Italics added).
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NASA and DARPA Plan 'Hundred-Year Starship' To Bring Humans to Other Worlds And Leave T... - 0 views
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If NASA ever gets a clear directive for interplanetary exploration, a new Hundred-Year Starship could be their version of the Mayflower. And like the first pilgrims, Martian explorers might set sail with the knowledge they would never return home.
'No fish left behind' approach leaves Earth with nowhere left to fish, study finds - 0 views
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ScienceDaily (Dec. 3, 2010) - Earth has run out of room to expand fisheries, according to a new study led by University of British Columbia researchers that charts the systematic expansion of industrialized fisheries.
Worst ever carbon emissions leave climate on the brink | Environment | The Guardian - 0 views
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Greenhouse gas emissions increased by a record amount last year, to the highest carbon output in history, putting hopes of holding global warming to safe levels all but out of reach, according to unpublished estimates from the International Energy Agency.
Lasers could power drones in flight or launch rockets | KurzweilAI - 0 views
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Researchers at LaserMotive have devised a way to beam lasers to power military bases and drones, possibly helping to save lives, since delivering fuel to battle zones can be a dangerous task in wartime. Although still largely in the R&D stage, laser power beaming has many other potential uses, which include powering vehicles, replacing electric power wiring and transmission lines in difficult places, and even launching rockets into orbit. The beam is about 8 inches wide as it leaves the transmitter - and then spreads wider as it travels. The beam emitter is located at a ground-based unit and operated by a person, who could control it from the same location or remotely from an entirely different place altogether. The operator uses the machine to fire the laser beam at a photovoltaic collector located on an unmanned autonomous vehicle (UAV), small plane, or helicopter. The current range of the system is about a kilometer. When the laser hits the photovoltaic device, the photons in the light beam are converted to electricity to fly the AUV. Topics: AI/Robotics | Energy | Physics/Cosmology | Survival/Defense
Description and Specification of Graphene - 0 views
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Graphene is a single-atom-thick sheet made from combined carbon atoms. The carbon atoms are bonded together to share electron in a hexagonal, honeycomb-like structure. It is a single atom thick layered 2D material ever discovered in the world. It is made up of a hexagonal lattice pattern of carbon atoms in a monolithic honeycomb-like structure. It is a layer of SP2 single bonded carbon atoms arranged like a chicken wire mesh. It is 200 times stronger than stainless steel (SS) and 100 thousand times thinner than the human hair. It is the slimmest and strongest compound available on the earth. Anybody would be amazed when they know that we have found a material which is harder than diamond, yet lightweight, stronger than steel, but also highly flexible, and this material can be mined from the earth as it occurs naturally. It is yet thin enough to be mistaken for a saran wrap. Apart from the optimum physical properties, the other features are also impressive. Properties of Graphene These are some prominent features which make it a hi-tech material: Excellent Electronic Conductor Chief electronic property makes it an efficient Zero-Overlap Semi metal and gives it sufficient electrical conductivity. Carbon atoms possess typically 2 electrons in the inner shell, and 4 electrons in the outer orbit, total 6 electrons. Although conventionally, the outer 4 electrons in carbon can connect with another atom, each, the atoms can form a 2-dimensional bond with three atoms per single atom. This leaves an electron available for electronic conduction. Such electrons are known as 'Pi' electrons and found above and below in sheet. Ultimate Tensile Strength Mechanical strength is another prominent property of the material. It considered as being the foremost most robust material ever discovered, owing to the 0.142 Nm-long carbon bonds. It also possesses ultimate tensile strength, measuring 130 Gigapascals (or 130,000,000,000 Pascals). Compared to the tensile strength of industr
Guest Post: Tom Levenson on Isaac Newton as the First Cosmologist | Cosmic Variance - 0 views
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To make his ambitions absolutely clear Newton used the same phrase for the title of book three. There his readers would discover “The System of the World.” This is where the literary structure of the work really comes into play, in my view. Through book three, Newton takes his audience through a carefully constructed tour of all the places within the grasp of his new physics. It begins with an analysis of the moons of Jupiter, demonstrating that inverse square relationships govern those motions. He went on, to show how the interaction between Jupiter and Saturn would pull each out of a perfect elliptical orbit; the real world, he says here, is messier than a geometer’s dream.
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