黑洞是一种引力极强的天体,就连光也不能逃脱。当恒星的史瓦西半径小到一定程度时,就连垂直表面发射的光都无法逃逸了。这时恒星就变成了黑洞。说它黑,是指它就像宇宙中的无底洞,

发表于:2019-01-26 / 阅读(65) / 评论(0) 分类 英语听力文摘 English Digest

Motional Induction Last time, we talked about motional induction , a phenomenon by which the ocean generate s a magnetic field. It works like this: earth has its own magnetic field. The ocean has plenty of charged atoms in it, in the form of dissolve

发表于:2019-01-26 / 阅读(58) / 评论(0) 分类 英语听力文摘 English Digest

Microneedles 微针疗法 Female: From flu vaccin es to tetanus booster s , injections are a must in modern medicine. But do they always have to make you say Ouch? Male: Eh,no? F: No,indeed.If new microneedle technology is successful, we may soon hav

发表于:2019-01-26 / 阅读(66) / 评论(0) 分类 英语听力文摘 English Digest

地球是太阳系从内到外的第三颗行星,也是太阳系中直径、质量和密度最大的类地行星。它也经常被称作世界。英语的地球Earth一词来自于古英语及日耳曼语。地球已有44~46亿岁,有一颗天然

发表于:2019-01-26 / 阅读(67) / 评论(0) 分类 英语听力文摘 English Digest

Is squinting really that effective? 眯眼睛真的有效吗? Male: Thanks for coming on this fact-finding trip with me and share the driving. Female: Glad to do it. It should be a fun trip. I imagine I will learn a lot. M: I hope so. So i think we

发表于:2019-01-26 / 阅读(63) / 评论(0) 分类 英语听力文摘 English Digest

a butterfly with glowing eyes Believe it or not, Monteiro and her team insert ed a new gene into the butterflys genetic sequenceone taken from a jellyfish . No, I know you're fooling. Actually I'm not. This gene codes for a green florescent protein t

发表于:2019-01-26 / 阅读(61) / 评论(0) 分类 英语听力文摘 English Digest

When Marmoset s Think About Love 小猴子表达如何爱 狨猴( Marmoset ),又称指猴,是生活在在南美洲亚马逊河流域的森林中的一种世界上最小的猴子。这种猴长大后身高仅1012厘米,重80100克。新生猴只

发表于:2019-01-26 / 阅读(51) / 评论(0) 分类 英语听力文摘 English Digest

对于外太空,亲,你知道多少呢?旅行者号,你知道吗?太阳风,你知道吗如果你的答案是no,那我们都是一样的哦,宇宙太奇妙,需要一代代人不断去探索.今天我们就来讲讲我们的太阳系 The Real Final Fro

发表于:2019-01-26 / 阅读(66) / 评论(0) 分类 英语听力文摘 English Digest

Carnivorous Bees 蜜蜂也吃肉? I guess you never heard of Trigona hypogea, a South American bee that not only collects meat from animal carcasses, but has more recently been discovered to have a taste for live prey as well. Scientists have seen

发表于:2019-01-26 / 阅读(45) / 评论(0) 分类 英语听力文摘 English Digest

M: Kids these days! They have no respect; they don't know the value of dollar;they can't pay attention to anything for long. F: Actually, that last one may be true. Well,the older generation always complains about kids. But researchers who study the

发表于:2019-01-26 / 阅读(58) / 评论(0) 分类 英语听力文摘 English Digest

Ya?l: Somebody bought my daughter a game called Cuddies. Don: I love that game! Y: I don't know about that. But the little plastic tongue-like part of that strange insect like body did inspire me to wonder about taste and insects. Do insects have t

发表于:2019-01-26 / 阅读(64) / 评论(0) 分类 英语听力文摘 English Digest

About six or seven million years ago chimpanzees and humans evolved from a common primate ancestor. Chimps went on to become the relatively small-brained, forest dwelling creatures we know and love. Humans went on to evolve large brains, spread throu

发表于:2019-01-26 / 阅读(50) / 评论(0) 分类 英语听力文摘 English Digest

Dear Annie: I have known Celia for five years and love her like a sister. A few months ago, I found out that Celia's husband is having an affair with a former employee. I know he meets this woman at variousout-of-the-way places and that he leaves wor

发表于:2019-01-26 / 阅读(76) / 评论(0) 分类 英语听力文摘 English Digest

Picture this: A foraging squirrel comes into range of a hungry, coiled rattlesnake. The squirrel realizes the danger too late--the rattlesnake strikes out and bites, fangs pumping venom deep into the squirrel's small body. The poison doesn't kill imm

发表于:2019-01-26 / 阅读(64) / 评论(0) 分类 英语听力文摘 English Digest

Think back to your college days, the good old days when life was easy. Stay up all night partying or even studying? No problem. Eat pizza every night and plow through entire bags of potato chips at one sitting. Hey, no sweat. You were a lean, mean, a

发表于:2019-01-26 / 阅读(82) / 评论(0) 分类 英语听力文摘 English Digest

婚姻的创伤 Anyone who's been married knows that arguing with your spouse comes with the territory. Those heady, romantic days of courtship have given way to arguing about doing the dishes and taking out the garbage. But, as any marriage counselo

发表于:2019-01-26 / 阅读(65) / 评论(0) 分类 英语听力文摘 English Digest

Not only does it soothe the savage beast, but music also makes unruly children calmer while at the same time honing their facilities for cognitive skills and physical coordination, according to a leading expert. A mother's soft lullaby, granddad's wh

发表于:2019-01-26 / 阅读(71) / 评论(0) 分类 英语听力文摘 English Digest

Dear Annie: Each year, the company my wife works for hosts a Christmas dinner party at a local restaurant. What used to be an enjoyable meal with a handful of employees has become a large, drunken event lasting late into the night. One year, two empl

发表于:2019-01-26 / 阅读(61) / 评论(0) 分类 英语听力文摘 English Digest

What's in store for tech fans in 2008? Plenty. Technology buffs can look forward to products that are better, faster and less expensive than those we rely upon today. The iPhone may have been the biggest tech product rollout of 2007, but that doesn't

发表于:2019-01-26 / 阅读(48) / 评论(0) 分类 英语听力文摘 English Digest

The mathematical marriage predictor. You might not think that mathematicians have anything particularly relevant to say about your love life. But you'd be wrong--if we're talking about James Murray, a mathematician at the University of Washington in

发表于:2019-01-26 / 阅读(52) / 评论(0) 分类 英语听力文摘 English Digest