Threshold 2: Stars Light Up Light travels fast. In one second it races around the Earth seven times. In 1.29 seconds, it reaches the Moon. In eight minutes, the Sun. And if that light keeps traveling for 93 billion years, it might cross the entire Universe, or it might still have a long way to go. The Big Bang involved scales of time and space so far beyond the dimensions we are familiar with that there is almost no way to describe it. Some astrophysicists call the next 200 million years the Dark Ages. Like the tiny knots in the grain of a wood board, there were tiny imperfections in the density and temperature of this uniform matter. Though he never could have guessed how stars formed, Isaac Newton may have admired Orion from his grandparents' garden during the summer of 1665. He had just received a degree in natural philosophy from Cambridge University, which then shut down due to outbreaks of the plague in London. This was the spark of a new idea: Newton's law didn't say why gravity exists, or how it exists.
Threshold 1: The Big Bang Two scientists with the best equipment available were getting nothing but interference. Maybe the pigeons were to blame. A flock of pigeons had taken to perching atop the big metal “horn” of their radio antenna near Holmdel, New Jersey, in 1964. Shaped like a giant ear canal 20 feet wide and 50 feet deep, the horn's smooth interior was designed to receive extremely faint radio signals from far off. The two scientists figured the droppings had to be what was interfering with their readings. They asked workers to clean out the pigeon droppings. Again they pointed the giant ear toward outer space and listened. By now they'd done everything they could think of to eliminate it. Nothing changed. The notion that the Universe might actually be expanding had been proposed at least since the 1920s but it was greeted by a great deal of skepticism from the very start. Einstein didn't agree. “Vos calculs sont corrects, mais votre physique est abominable,” he remarked in French to Lemaître.
BBC Radio 4 - Out of the Ordinary, Series 1, Episode 2 Gianduja (chocolate) Gianduiotti, a speciality of Turin, are chocolates shaped like an upturned boat, again made with a mixture of cocoa and hazelnut paste. Invented by Caffarel in 1852, it is still a trade mark for the companyNutella, which was originally called Pasta Gianduja.[3] World History Threshold 3: New Chemical Elements Likewise, Aristotle's geocentric view of the Universe had a very long shelf life. More than 400 years after Aristotle, Claudius Ptolemy was merely refining the great philosopher's cosmological theories, describing a model of a Universe that still showed the Earth at its center and, as one moved outward, a series of concentric spheres containing the Moon, the planets, the Sun, and finally the “sphere of fixed stars.” And centuries after that, Ptolemy's geocentric model and his Almagest – a treatise on the paths of planets and stars – still dominated the thinking at Europe's medieval universities. Meanwhile, alchemists and philosophers continued to explore the nature of matter. By many measures, the era of modern science started in the 1500s, when Nicolaus Copernicus challenged the geocentric model. An astute observer, Copernicus refined the calculations and reopened the debate. Begin with a pebble. A silicon atom has 14 electrons flying around its nucleus.
Big Bang Nucleosynthesis The big bang models - the cosmological models based on general relativity - tell us that the early universe was extremely hot and dense. At the earliest stages that can be modelled using current physical theories, the universe was filled with radiation and elementary particles - a hot plasma in which energy was distributed evenly. During the subsequent expansion, this plasma has progressively cooled down. By examining how the cooling affects the matter content of the universe, one can derive one of the most impressive testable predictions of the big bang models. Nuclear physics in an expanding universe As the universe cools, the matter content changes - new particles are formed out of the preexisting ones, such as protons and neutrons forming out of quarks. While the early universe is totally unlike our everyday world, the basic nuclear physics at the appropriate energies is well within the range of laboratory experiments. Theory and observation [Adapted from an image by E.
Diana Deutsch's Audio Illusions 25 Strangest Geological Formations On Earth ИСТОРИЯ ДРЕВНЕГО МИРА Protons, Neutrons, and Electrons | Chapter 4: The Periodic Table & Bonding Show a picture of a pencil point and how the carbon atoms look at the molecular level. Project the image Pencil Zoom. Students should be familiar with the parts of the atom from Chapter 3 but reviewing the main points is probably a good idea. Ask students questions such as the following: What are the three different tiny particles that make up an atom? Show the simulation Balloons and Static Electricity from the University of Colorado at Boulder’s Physics Education Technology site.