标签：小行星 相关文章
French researchers are predicting doom for Planet Earth. They believe neighboring planets could stray out of orbit and collide with the Earth billions of years from now. The BBC's David Shukman explains their theory. A view of Earth from orbit and a
万花筒2009年
In 2017, European scientists plan to go on a very special space mission - landing on an asteroid. But why do they want to visit an asteroid and will there be space for Callum on the spacecraft?! 欧洲科学家计划于 2017 年进行一次航空任务 - 降落在小行
六分钟英语
Police say an adult aide and 2 children have died when 2 school buses collided on a Tennesse highway Tuesday. Another 27, mostly children, were injuried in the crash that left one of the buses on its side. Hundreds of survivors took to the streets in
美联社新闻一分钟2014(十二)月
NASA Chooses Boeing, SpaceX to Fly Astronauts 美国航天局联手波音及SpaceX两公司共建太空船 Three years after the United States ended the space shuttle program, the American space agency today announced the return of human space flight
2014年VOA慢速英语(九)月
A meteorite bursting through the atmosphere over Russia injuring hundreds of folks on the ground. It happened overnight in the fringe of Siberia, sending shock to residents into a state of panic. ABC's Current Rania filed this report just moments ago
万花筒2013年
It's very hard to tell. We've just hit the water. It's very hard to tell what altitude we're at. We've crashed the airplane at 930 feet. It seems clear that flying into that methane caused enough confusion in the instruments and with Thomas and he en
自然百科2010年
Don: It's time once again for one of those Moments of Science that we like to call Never Thought to Ask.Our never thought to ask question for the day is: Why is the earth round? Ya?l: Why is the earth round? I never thought to ask that. D: Of course
英语时差8，16
An asteroid strike would create a huge explosion. NASA feared this might even be mistaken for a nuclear bomb. We wanted folks to know this was a natural event by Mother Nature rather than some sort of man-made event like a missile or something dreadf
探索与发现2014年
Comparing the effects of an airburst with a ground strike, it seems the Chelyabinsk got away lightly. Its estimated that the largest piece to hit the ground weighed 500 kilos, a fraction of the asteroids original mass of 7,000 tonnes. Now if a piece
探索与发现2014年
Tim has developed a map to visualize their location. And on that map, the most important are the Near-Earth asteroids, the ones closest to the planet. On the screen here is a map of the solar system. And Ive got the Sun in the centre and the third pl
探索与发现2014年
Weknew from the radar measurements where Golevka was within a few tens of metres.And yet it was actually 12 or 15 kilometres away from where it was predicted tobe without Yarkovsky effect. So these very precise radar observations allowedus to see the
探索与发现2014年
Heset out to investigate a hundred-year-old theory that said asteroids werepowered by the Sun itself. It was called the Yarkovsky effect. The Yarkovskyeffect is a very small acceleration and acts on asteroids and what it is is ifyou take a model, the
探索与发现2014年
Itsremarkable how we are able to build up this picture of whats going on millionsof miles away in the solar system. Its one of the joys of science really, justalmost like a detective picking up on those tiny clues to tell a bigger story. Sothat the b
探索与发现2014年
I was shocked. I was truly shocked. I never thought Iwould see an event like this over a major city during my lifetime. We couldnt predict this was going to happen. The pieceof rock that actually entered the atmosphere was relatively small, maybe onl
探索与发现2014年
Amazing images. But what can you get out of these asan expert? What it shows us, first of all, is a great record ofthe entry of the object into the Earths atmosphere. So you see it right fromthe moment it really penetrated. And there it is. That is t
探索与发现2014年
Its been said that the first person on Mars is alive somewhere on earth today. Imagine its you. What do you need to know? How much you get there? What should you pack? What are some of the must-see sights and what should you avoid? Think of this as y
自然百科2012年
NASA Contractor Shows New Technology Despite the daunting debt problems faced by the U.S. government, many federal operations, including the Defense Department and the space agency, NASA, need the latest technology to carry out their missions. That t
VOA标准英语2011年(十月)
But still be able to use your hands. Not only will you want to move your fingers, you want to move around. NASAs lunar electric rover is a prototype for future missions to the moon and Mars. Its part vehicle and part space suit. I can just picture be
自然百科2012年
Shaw, listed by Forbes as a billionaire, was also a generous philanthropist who was knighted by Britain's Queen Elizabeth in 1977 for his public service as a long-time backer of the Red Cross. 40 years ago he established the Shaw Foundation which is
CCTV9英语新闻2014年01月
台湾籍旅美老师今天交给我们的句子是： Many scientists believe that the extinction of dinosaurs was caused by an asteroid the size of a small town crashing into what is now Mexicos Yucatan peninsula. 很多科学家认为恐龙的灭亡
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