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These holes are the unmistakable hallmark of a violent death. Their shape suggest they were made by the teeth of a big cat, but which one? Today theres only one large cat in the region, the Florida panther. Though similar to the cougar at the western
探索与发现2012年
But how did one man and a spear produce the huge force behind this blow? The answer lies with small bits of ivory like this. They were once part of an atlatl, or spear thrower. An atlatl acts as a sort of catapult, magnifying the strength of a hunter
探索与发现2012年
BBC: Genius of the Ancient World | 《英国广播公司：古代世界的天才》 第一集 Buddha 古代圣贤：佛祖释迦牟尼 历史学家贝特妮休斯（Bettany Hughes）游历印度、希腊、和中国以追寻三位古代世界的哲学巨
探索与发现2016年
For the Buddha, the rigid hierarchy of the caste system and sacrifices to the gods relied on blind faith and received wisdom, not any kind of rational explanation. He passionately thought that must be a more robust, a more credible way to understand
探索与发现2015年
A lone wolf weighs as much as four coyotes, but one on one it's still no match for a bison. Wolves, though, live and hunt in packs of up to 15 and when they launch a cooperative attack, they're devastating. First they get the bison on the run, then f
探索与发现2012年
When you consider the Earths history stretching over billions of years, its clear that meteorite impacts, far from being unexpected, are just a normal part of the life cycle of our planet. But that is not how they seem to us. The Chebarkul meteorite
探索与发现2014年
It came in in the daytime sky out of the Sun. Weve got telescopes looking out there for these objects, but they only work at night. Radar doesnt help either because to really use radar to find these objects above the atmosphere, you have to know exac
探索与发现2014年
Approaching from beneath the planet, asteroid 2012 DA14 passed inside the orbit of our geostationary satellites before heading off to the north. This asteroid had been successfully tracked for a year. And despite its proximity, scientists knew that i
探索与发现2014年
There it is! Yep. Its about 90 kilometres up, at that stage, travelling at 17.5 kilometres per second. Using the different camera positions, scientists have pinpointed the exact position at which the meteor entered the atmosphere. And by tracking the
探索与发现2014年
Most of the damage from an explosion like this is actually the blast wave. Its the very high winds. Mark created a simulation to see what size an asteroid would need to be to be able to generate such destructive power. In this simulation I include mo
探索与发现2014年
So this was serial number one. It was built during the Apollo time. I guess because they thought there would be several of them made, but this is the first one and the last one and is the only one like it in the world. This is NASAs Vertical Gun Rang
探索与发现2014年
Look at the size of this! This is magnificent! That is beautiful. This cave may be stunning, but it provides the evidence for one of the greatest catastrophes in the Earths history. And that water, its so clear! Lower the gear, please! Theres actuall
探索与发现2014年
The meteorite was 15 kilometres across, enough to cause utter devastation across the whole planet. It exploded with a force of 100 million million tones of TNT. The blast sent a giant plume of vaporized rock out into space. A crater was punched 30 ki
探索与发现2014年
On 6th October 2008, asteroid hunter Richard Kowalski saw something that would change the assessment of threats presented by asteroid impacts. The night was proceeding normally and up on the screen came another asteroid. As I continued to make observ
探索与发现2014年
Well,the early reports are that it is an ordinary chondrite and that means it willbe similar to this one. So this is really exciting for us as scientists becausewe want to know how the planets formed, what was around before the planets, whatthe envir
探索与发现2014年
Meteor strikes as big as this may be rare butscientists have a surprisingly detailed knowledge of what meteorites are andwhere they come from. Long before the meteorite reached its explosivefinale in full view of Chelyabinsks dash cams, it had a very
探索与发现2014年
By collecting and comparing meteorites, scientistshave been able to piece together a picture of how they form and these studieshave revealed some of the most remarkable rocks in the solar system. Few places in the world have got as many meteoritesas
探索与发现2014年
So, Ben and Deber just decided to live as common long man and wife. With his personal life stabilized, Franklin jumped into the newspaper business. He buys the Pennsylvanian giz and becomes the founding father of another American tradition--- the sex
探索与发现2014年
第一集 Buddha 古代圣贤：佛祖释迦牟尼 历史学家贝特妮休斯（Bettany Hughes）游历印度、希腊、和中国以追寻三位古代世界的哲学巨人佛祖释迦牟尼、苏格拉底和孔子的足迹。她首先来到印度；当
探索与发现2015年
古代圣贤：佛祖释迦牟尼 历史学家贝特妮休斯（Bettany Hughes）游历印度、希腊、和中国以追寻三位古代世界的哲学巨人佛祖释迦牟尼、苏格拉底和孔子的足迹。她首先来到印度；当年，佛祖离
探索与发现2015年