Steven Jabs search for remaining fragments, using a custom-built metal detector rig. Meteorites will have iron in them, and it's ? So not only will magneticbe attract to it, but also metal detector will be able to pick it up. Every year, over eightee

发表于:2018-12-03 / 阅读(63) / 评论(0) 分类 探索与发现2014年

As the balloons rise higer still,they face an attact by an invisible bombardment,radiation.Every day the Sun radiates a titanic amount of energy,some of them in the form of high energy of ultra violet rays.These rays packed a powerful punch ,and in t

发表于:2018-12-03 / 阅读(56) / 评论(0) 分类 探索与发现2014年

But the friction and heat wears away at the space rock, the hot air actually melts the metal surface, and often the collision with the atmosphere can have a shattering effect, splitting the meteorites along fissures. This is an actual meteorite, and

发表于:2018-12-03 / 阅读(71) / 评论(0) 分类 探索与发现2014年

And above it the fragile air of the mesosphere is shielding us from a another deadly barrage from space. In east Texas, Jeff and Steve are searching for the remains of cosmic missiles that have been shattered by our atmosphere, fragments rarer than d

发表于:2018-12-03 / 阅读(72) / 评论(0) 分类 探索与发现2014年

诸多线索综合起来为我们描绘出一幅画面:那是火星遥远的过去,那时的火星还有着一层厚厚的大气层,令这颗星球温热暖和,从而使水能够在火星表面流淌。但如今,地表的水消失不见,而

发表于:2018-12-07 / 阅读(98) / 评论(0) 分类 60秒科学

he people who, who work on the origin of life 今天研究地球生命来源的专家认为 on earth today seem to have come to the conclusion 海底的高热火山口 that the most likely place for life to have begun 是最可能开始出现生命的地

发表于:2018-12-07 / 阅读(159) / 评论(0) 分类 神秘的月球

The Earth's Biggest Threat 地球危机──温室效应 by Levi King Global warming was once considered unlikely to be real. Recently, though, it has become widely accepted as fact. Scientists have calculated that the earth's atmosphere has gotten

发表于:2018-12-08 / 阅读(55) / 评论(0) 分类 常春藤解析英语

You could use the balloons not just to go to the edge of the space as we do now,but go all the way over the line, and actually to use balloons or airships to go all the way into space,space travel without rocket.Officially, the atmosphere ends and sp

发表于:2018-12-27 / 阅读(44) / 评论(0) 分类 探索与发现2014年

But to fully forecast the floods, he needs a lot more atmospheric data. He believed robotic drone aircrafts developed for the military could continue to measure the air over the oceans, charting its temperature, wind and humidity. And the flight coul

发表于:2018-12-27 / 阅读(47) / 评论(0) 分类 探索与发现2014年

A single river can carry three times as much water as the entire Mississippi, they provide almost half the annual rain fall for parts of the American Pacific coast, but when they remain in one area for a day or more, they can produce violent flooding

发表于:2018-12-27 / 阅读(61) / 评论(0) 分类 探索与发现2014年

[00:05.69]telecommunication [00:07.52]n.电信 [00:09.35]via [00:10.83]prep.经由,经过,通过 [00:12.30]satellite [00:13.62]n.卫星,人造卫星 [00:14.94]transmit [00:16.56]vt 1.播送 2.传递 3.输送 [00:18.18]photography [00:19.57]n. 1摄影 2摄影术 [00:20.95]

发表于:2018-12-29 / 阅读(133) / 评论(0) 分类 大学英语自学教程上

What Are Solar Tornadoes? Large, Earth bound tornadoes are pretty impressive weather events. Those dark, giant funnel clouds inspire much awe and fear. But theyre nothing compared to so called solar tornadoes solar gases swirling in monstrous formati

发表于:2018-12-31 / 阅读(64) / 评论(0) 分类 英语听力文摘 English Digest

And then our mothers tell us, Careful you don't fall down, because you'll fall over. 然后母亲告诉我们,没有跌倒也要小心,因为你还会掉下来。 Now, go into the real atmosphere of this planet. 现在,进入这个行星真正的

发表于:2019-01-18 / 阅读(99) / 评论(0) 分类 TED演讲娱乐篇

Back in January, one of California's oldest and most iconic residents keeled over: the Pioneer Cabin tree, a giant sequoia in Calaveras Big Trees State Parkso big you used to be able to drive through it. 在今年一月份,加州一座最古老、最

发表于:2019-01-20 / 阅读(76) / 评论(0) 分类 2017年Scientific American(三)月

The planet also began releasing oxygen, thanks to an ancient adoption of photosynthesis. A very ancestral primitive plant cell either engulfed or tried to digest or surrounded a cyanobaterium and instead of digesting it, it actually became an organ w

发表于:2019-01-23 / 阅读(93) / 评论(0) 分类 探索与发现2014年

This is Xaero - a vertical take-off and landing vehicle being developed by Masten Space Systems. The California start-up hopes the rocket will eventually carry pay-loads for NASA to altitudes of up to 30 kilometres, mainly to collect atmospheric data

发表于:2019-02-03 / 阅读(59) / 评论(0) 分类 英语新闻视频

Reentry Heat [Why does a space shuttle get hotter on reentry than on liftoff?] 能想象航天飞机穿越大气层时受到摩擦产生的热量有多惊人吗?来一起听听吧。 M:Dolle,we now know that the space shuttle Columbia burned up whe

发表于:2019-02-24 / 阅读(71) / 评论(0) 分类 英语听力文摘 English Digest

Even so, spaceships have to take care in the outer atmosphere, particularly on return trips to Earth, 即使这样,宇宙飞船在外层大气也不得不小心翼翼,尤其是在重返地球的过程中。 as the space shuttle Columbia demonstra

发表于:2019-02-25 / 阅读(103) / 评论(0) 分类 万物简史

As anyone who has used such a pump knows, compressed air grows swiftly hot, 使用过打气筒的人都知道,受到压缩的空气马上会变热, and the temperature below it would rise to some 60,000 Kelvin, or ten times the surface temperatur

发表于:2019-02-25 / 阅读(66) / 评论(0) 分类 万物简史