This is a genuine iron meteorite, this is believed to have once been part of the core of a long dead planet or asteroid, and this was found right here in this strewn field, this remarkable little shapes, indentations on the surface are called thumbpr

发表于:2018-12-03 / 阅读(66) / 评论(0) 分类 探索与发现2014年

bubbles in the atmosphere.On other planets with denser atmospheres,larger, more complex creatures can take to skies.The thick air could support them alofty,allowing bulky reptiles to fly and glide.This creature probably couldn't be able to fly very l

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

scores of sciencse experiments on board the airship study the dramatic persure change. we call it punset for pingpang ball satelite, and it also be the first thing we do is to have cut the pingbang ball on air ,then your experiment goes inside. and s

发表于:2018-12-03 / 阅读(61) / 评论(0) 分类 探索与发现2014年

One day these manned space missions may reach out even further to distant planets with alien atmospheres, atmospheres that may support their own life forms. Else where in our universe on distant planets, alien air may support extraterrestrial life. J

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

67 第一架飞离大气层的飞机--X-15 EXPLORATIONS - September 12, 2001: X-15 PlaneBy Marilyn Rice Christiano ANNCR: EXPLORATIONS -- A PROGRAM IN SPECIAL ENGLISH BY THE VOICE OF AMERICA. (THEME)

发表于:2018-12-09 / 阅读(76) / 评论(0) 分类 自然探索

The global average could be up 7 degrees F by the end of the century, wreaking havoc with weather patterns and habitats. We can't prevent climate change by preserving the air's delicate blend of gases, the unique mix that sets earth apart. And our pl

发表于:2018-12-27 / 阅读(58) / 评论(0) 分类 探索与发现2014年

The air thins and they begin to lose the protective weight of the miles of air above them. The pressure is dropping, when you finally get to the stratosphere, and to the altitude we like to work at, it's only one one hundredth that of it's on the gro

发表于:2018-12-27 / 阅读(67) / 评论(0) 分类 探索与发现2014年

The planet's rotation twists the air as it flows, helping form the hurricanes that lash the coasts. As moist air wells upwards, clouds become electrically charged and send lightning bolts crushing down to the earth, superheating the air to eighteen t

发表于:2018-12-27 / 阅读(45) / 评论(0) 分类 探索与发现2014年

Our atmosphere is in constant motion; the moving air that causes our weather circulates between the ground and 50,000 feet. It is the sun that drives this movement. When solar energy reaches earth, it heats the surface and atmosphere, but it does so

发表于:2018-12-27 / 阅读(66) / 评论(0) 分类 探索与发现2014年

Using science as a guide, we attempt to recreate the final moments of the dinosaurs. 我们以科学为指引,试图重建恐龙的最后时刻。 The first effect was the impact itself. 第一个效果是撞击本身。 So when a 10-kilometer diam

发表于:2018-12-28 / 阅读(41) / 评论(0) 分类 侏罗纪搏击俱乐部

Evidence of the first oxygen in the atmosphere. The gas was released by a humble microscopic living organism called cyanobacteria. Well it turns out cyanobacteria are the only things that can actually produce oxygen, so we know that at some point cya

发表于:2019-01-23 / 阅读(54) / 评论(0) 分类 探索与发现2014年

We were left with this atmosphere made of molten rock and vaporous rock. It took millions of years for that atmosphere to fall out and to be replaced by an atmosphere made up of nitrogen and carbon dioxide and water vapour. These new gases came from

发表于:2019-01-23 / 阅读(63) / 评论(0) 分类 探索与发现2014年

Our planet was spared this fate. The magnetic field generated by the Earths core blocked the solar wind, preventing it from blasting away the fragile air. But the Earths atmosphere was still very different from the one we breathe today. It contained

发表于:2019-01-23 / 阅读(58) / 评论(0) 分类 探索与发现2014年

To discover why these twin planets followed separate paths and to explore what gave us our precious atmosphere, we have to travel back, back four and a half billion years to the birth of the solar system itself. The birth of the solar system created

发表于:2019-01-23 / 阅读(56) / 评论(0) 分类 探索与发现2014年

In contrast, Jupiter and Saturn are all atmosphere. Unlike Earth, Jupiter doesnt really have a solid surface that you could stand on and then have your head up in the atmosphere looking at the clouds. Its just a giant, giant gas ball. Only one other

发表于:2019-01-23 / 阅读(52) / 评论(0) 分类 探索与发现2014年

英语听力,探索发现,科学新发The mission had been a stunning success: Kittinger skydiving record stands to this day. He takes his first deep breath of air with a new found appreciation for our atmosphere. It was relief to be back on the plan

发表于:2019-01-23 / 阅读(64) / 评论(0) 分类 探索与发现2014年

Kittinger is in the mid stratosphere, a record 102,800 feet high. And it is now the time to make the long, swift journey down. When it came time for me to jump, I was ready to jump because I was heading back toward a more friendly environment, a frie

发表于:2019-01-23 / 阅读(67) / 评论(0) 分类 探索与发现2014年

My crew chief said, are you ready? I said, Im ready, lets go. It was a very smooth take-off and I started ascending up, up, up. 30 minutes after take-off, Kittinger reaches 29,000 feet, the middle of the troposphere. At this altitude, the air is so t

发表于:2019-01-23 / 阅读(57) / 评论(0) 分类 探索与发现2014年

Our chemistry, our very nature, our metabolism is completely shaped by the atmosphere. To appreciate our atmosphere, well rise through its layers, travelling from the planets surface, miles up above mountains and the clouds, to the very edge of space

发表于:2019-01-23 / 阅读(49) / 评论(0) 分类 探索与发现2014年

In the empty blackness of space surrounded by hostile planets and freezing vacuum, planet Earth is an oasis of life. And all because of our protective cocoon of gas. This blanket of air shapes everything we see on Earth. It protects, insulates and su

发表于:2019-01-23 / 阅读(41) / 评论(0) 分类 探索与发现2014年