Supermassive Black Holes 超大质量黑洞 - 13

Silk realized that the energy from this newly formed quasar would create intense temperature changes in the surrounding gas. This would cause the gas around the black hole and its newly formed quasar

Supermassive Black Holes 超大质量黑洞 - 12

This correlation is the most important thing we've learned about supermassive black hole so far. Astronomers are always looking for correlations. Whenever you find one that's really tight like this on

Supermassive Black Holes 超大质量黑洞 - 10

If, as it now seems, every single galaxy has a black hole at its heart, this can't be a coincidence. Perhaps black holes are an essential part of what galaxies are and how they work. No one had expect

Supermassive Black Holes 超大质量黑洞 - 11

Those stars don't feel the black hole. They feel the rest of the stars in the galaxy. They don't know or care that the black hole is there. If you took the black hole away from the galaxy, they would

Alien Neighbors 寻访外星人 13

Alien Neighbors 寻访外星人 14

Alien Neighbors 寻访外星人 12

How likely that technology will destroy those who invented it? The Drake Equation doesn’t exactly narrow the field. Depending on the variables, the number of intelligent civilizations could be zero

Alien Neighbors 寻访外星人 10

…cold conditions that earth has to offer. Professor Freeman believes these rugged microorganisms are probably capable of surviving on Mars. Mars is certainly our best bet for finding life in the inn

Alien Neighbors 寻访外星人 9

He wears gloves and cleans his tools with alcohol to avoid contaminating the ancient salt samples with modern microorganisms.

Alien Neighbors 寻访外星人 11

We have reasons to suspect, based on recent high resolution photography of the surface, that there may be a subsurface ocean there. And where we find water and where we find the right mix of organics,

The Human Body: Life Story 生命物语-9

Millions of years ago, the embryo of a distant ancestor of ours would have shared with us many of these features. As well as giving rise to us, it gave rise to all sorts of other creatures. And in tho

The Human Body: Life Story 生命物语-10

It is incredible, and it is incredibly hard to believe too, because although we've changed so much, we don't actually see any of those changes happening. Generation after generation, we just look the

The Human Body: Life Story 生命物语-11

But what's even more amazing to me is that although we've changed so little in so many thousands of years, each of us changes so much in just one lifetime. We tend to think of growing up as just getti

The Human Body: Life Story 生命物语-12

But if I were to tell you just the science of these changes I would be missing the most important thing of all. Let me show you what I mean. This is the amount of tears that an average person cries du

The Human Body: Life Story 生命物语-13

(Come on, let's talk about sex, baby, let's talk about you and me, let's talk about...) When it comes to growing up, 12-year-old Beatrice will ride the roller coaster of puberty . (let's talk about se

The Human Body: Life Story 生命物语-14

And I like this 'coz everybody see that a human being can manage an illness like my illness. And everybody can see in this film there is a way to make known the best from your end of your life. So thi

Wild Europe - Genesis 肇始之初- 14

Despite this enormous flood, the Mediterranean took more than a century to refill. But what is more amazing is that this process of drying and flooding has happened not just once, but possibly ten tim

Wild Europe - Genesis 肇始之初- 13

As the sun beat down, something like 4,000 cubic kilometers of water evaporated from the Mediterranean surface every year. And with no Atlantic water to replenish it, the Mediterranean dried out. In j

Wild Europe - Genesis 肇始之初- 12

...Africa. The African plate has been drifting north over millions of years. And when it pushes against the European plate, huge fold s of rock have been forced up and over one another into great moun

Wild Europe - Genesis 肇始之初- 11

...and marked the growing pains of a young ocean. 16 million years ago, North America and Greenland finally split apart from Europe. As the continental plates separated, the North Atlantic was born. I