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A Stationary Satellite, part 2 A geostationary satellite orbitsthe planet at the same rate as the planet rotates, so the satellite is always over the same patch of ground. Cool! you say. Id like to have one of those about twenty feet over my house. S
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A Stationary Satellite, part 1 Some of the best devices in science have been anticipated by science fiction writers years before they existed. Occasionally a writer comes up with an idea that can be put into practice within their lifetime! Such is th
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What Are Reflexes? If youve ever blinked at a sudden light, jerked your hand away from something hot, or jumped at a loud noise, then you know that these are not actions we consciously plan. Rather, they happen involuntarily. Such sudden, unconscious
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Everyone knows the story of the Titanic, the great ocean liner that struck an iceberg and sank to the bottom of the Atlantic. Less widely known is the icebergs story: where did it come from, and how did it get in the way of the ship? Although the vas
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In the early 1800s, a French physician named Ren Laennec had a dilemma. He needed to listen to the heart sounds of a young woman with signs of heart disease. But the only method of listening to heart sounds known to Western medicine at the time was s
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Scientists have searched for the origins of human speech in the hoots, grunts, and other vocalizations made by primates. It would seem to make sense, after all, that such sounds may be related to the more varied and articulated sounds we humans make.
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The Mathematics Of Middle-Age Spread Lets say youre an 18 year old male who runs every other day, logging 12 miles a week. Now fast-forward to your late 40s. Your eating habits are the same. To maintain your high school weight, how many miles a week
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Why refrigerators hum? Why refrigerators hum，on toay's moment of science.On the recent program we have discussed how fluorocarboncoolant cools your food by coming to a boil in coils hidden in your fridge. How is this possible? When you boil water o
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Why do Stradivarius violin s sound so good? 为什么史特拉第瓦里小提琴声音那么美妙？ A:What did i tell you？ B:You're right Yaoyao.This is a beautiful piece. A:It should be. B:What's so special about Stradivarius violin s ? A:Thats
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Bradycardia Don: Yal, isn't normal heart rate somewhere between sixty to one hundred beats per minute？ Yal: That's right, Don. Why? D: This would be the one time you don't correct me. My heart rate is only 44 beats per minute. That means I have bra
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Are Tanning Beds Safe? Millions of people go to tanning salons, some to get a base tan before they go away on a beach vacation. The idea of the base tan is that it will protect you from burning on your sun excursion, so that what you end up with is a
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As the Sun Turns 太阳也在自转？ Everyone knows that the earth turns. As a matter of fact, the sun turns too. Altough a lot of people don't realize it. Im not talking about being in orbit , nowthe earth definitely orbit s the sun and not the ot
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Why is it that you cant put down hydrogen gas? If you had a big balloon full of hydrogen gas, like the first gondola balloons pioneered in 18th-century France, youd find that it rises in the air quite dramatically. You know that a piece of wood will
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Frozen Smoke 固体烟 Male: What's as light as smoke but strong as a brick? Female: I'm gonna take a while guess and say... aerogel ? Male: Sorry,yaoyao,the answer is... Wait a second! Did you say aerogel ? How did you know? F:Yeap! Did you know tha
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Fidel Castro retires after 49 years in power 执政四十九年，古巴强人卡斯楚宣布退休 Ailing Cuban leader Fidel Castro said in a statement on Feb. 19 that he would not return to lead the country as president or commander-in-chief, retir
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For most of its running time, Secret lives up to its marketing as a sappy, beautifully shot and competently directed love story featuring Taiwan's own Jay Chou, the singer turned actor and now first-time director and screenwriter. Following a convent
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More and more women have began smoking in the last few decades. One of the reasons is savvy marketing as Don explains to Yael in this Moment of Science. D: Yael, what's that in your hand? Y: Come on, Don. Haven't you seen a cigarette before? Every da
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Yael: Don, are you eating my tulips? Don: Just having myself a little snack. Y: Of MY tulips? I brought those in here to brighten the place up, not for you to eat! And who eats flowers anyway? D: Have you seen that movie, Monsoon Wedding? There's a c
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One thing we're proud of here at A Moment of Science is that there isn't a lot of sex and violence on our program. Although, did you ever stop to wonder why sex and violence so often go hand in hand? How come nobody complains about violence and garde
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As ghost stories go, it's frankly a bit weak. Not very frightening and with a happy ending, it doesn't really prove the existence of the supernatural either. But it does show beautifully the enduring popularity of the offbeat and wacky on the interne
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