Best content in International Teacher Certificate

Fastest Skydiver Joseph Kittinger
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I heard that a man jumped from a balloon at the edge of space and broke the sound barrier during his fall. Who was he and when did this happen?
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16 August 1960, Kittinger jumped from a balloon high in the stratosphere to make the longest skydive from the highest altitude in history
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He did reach a peak velocity of 614 mph (988 km/h)
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Excelsior III helium-filled balloon and reached a new record altitude of 102,800 ft (31,330 m)
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sharp pain in his right hand due to a failure in the glove of his pressure suit
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three times higher than a commercial airliner typically flies
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Kittinger experienced air temperatures as low as -94°F (-70°C)
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why so many sources mistakenly claim that Joseph Kittinger broke the sound barrier during his 1960 skydive
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BBC News - Nature's hidden prime number code - 0 views

www.bbc.co.uk/...magazine-14305667 science biology math prime numbers evolution natural selection cryptography

shared by Massimo Boscherini on 06 Aug 11 - No Cached

Buzzing quietly beneath the planet we inhabit is an unseen world of numbers, patterns and geometry. Mathematics is the code that makes sense of our universe.
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But every 13 years, the banjos and basses get drowned out for six weeks by the chorus of an insect that has fascinated me ever since I became a mathematician. Only found in the eastern areas of North America, this cicadas survival depends on exploiting the strange properties of some of the most fundamental numbers in mathematics - the primes, numbers that are only divisible by themselves and one.
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This choice of a 13-year cycle doesn't seem too arbitrary. There are another two broods across north America that also have this 13-year life cycle, appearing in different regions and different years. In addition there are another 12 broods that appear every 17 years.
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You could just dismiss these numbers as random. But it's very curious that there are no cicadas with 12, 14, 15, 16 or 18-year life cycles. However look at these cicadas through the mathematician's eyes and a pattern begins to emerge. Because 13 and 17 are both indivisible this gives the cicadas an evolutionary advantage as primes are helpful in avoiding other animals with periodic behaviour. Suppose for example that a predator appears every six years in the forest. Then a cicada with an eight or nine-year life cycle will coincide with the predator much more often than a cicada with a seven-year prime life cycle.
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The cryptography that keeps our credit cards secure when we shop online exploits the same numbers that protect the cicadas in North America - the primes.
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The reason this is so secure is that although it is easy to multiply two prime numbers together it is almost impossible to pull them apart.
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The primes are the atoms of the arithmetic. The hydrogen and oxygen of the world of numbers.
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We know primes go on for ever but finding a pattern in the primes is one of the biggest mysteries in mathematics. A million-dollar prize has been offered to anyone who can reveal the secret of these numbers.
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