I want to talk to you about something kind of big. We'll start here. Sixty-five million years ago --
我想和大家探讨一样东西 一个庞然大物 我们先从这里讲起 6500万年前
(Laughter)
恐龙们倒了大霉了
the dinosaurs had a bad day.
(众人笑)
(Laughter)
一块长达6英里的巨石
A chunk of rock six miles across, moving something like 50 times the speed of a rifle bullet, slammed into the Earth. It released its energy all at once, and it was an explosion that was mind-numbing. If you took every nuclear weapon ever built at the height of the Cold War, lumped them together, and blew them up at the same time, that would be one one-millionth of the energy released at that moment. The dinosaurs had a really bad day. OK?
以出膛子弹50倍的速度 向前运行 当头撞上了地球 一时间 它释放出了所有能量 爆炸所产生的威力 令人无法想象 如果将冷战最紧张时期 所有核武器 堆成一堆 再同时引爆 所产生的威力 充其量还只是其百万分之一 恐龙们真是倒了大霉了 对吧
Now, a six-mile-wide rock is very large. We all live here in Boulder. If you look out your window and see Longs Peak -- you're probably familiar with it -- now, scoop up Longs Peak and put it out in space. Take ... Meeker, Mt. Meeker. Lump that in there, and put that in space as well. And Mt. Everest. And K2. And the Indian peaks. Then you're starting to get an idea of how much rock we're talking about, OK? We know it was that big because of the impact it had and the crater it left. It hit in what we now know as Yucatan, the Gulf of Mexico. You can see here, there's the Yucatan Peninsula, if you recognize Cozumel off the east coast there. Here is how big of a crater was left. It was huge.
一块6英里宽的巨石非常大 我们都住在Boulder市 从窗外看去 你可以看见 朗斯峰 你们对这山都不陌生吧 把朗斯峰连锅端起来 把它放到外太空 把米克山也拔起来 放到外太空去 再加上珠穆朗玛峰 乔戈里峰 印第安山脉群峰 现在你们应该可以想象 这块巨石有多大了吧 我们从爆炸释放的威力和之后留下的陨坑 得知这块巨石的确有这么大 它所撞击的地点 是现位于墨西哥湾的尤卡坦 你可以看这里 如果你认得东海岸的科祖梅尔岛 这里就是尤卡坦半岛 留下的陨坑有这么大
To give you a sense of the scale ... there you go. The scale here is 50 miles on top, a hundred kilometers on the bottom. This thing was 300 kilometers across -- 200 miles -- an enormous crater that excavated out vast amounts of earth that splashed around the globe and set fires all over the planet, threw up enough dust to block out the sun. It wiped out 75 percent of all species on Earth. Now, not all asteroids are that big.
它非常大 你可以估计一下它的大小 你看 它上面宽50英里 下面宽100公里 跨度为300公里 也就是200英里 这个巨大的陨坑 把大量泥土掘起 抛散开来 尘土弥漫 整个地球四处起火 烟尘遮盖了阳光 地球上75%的物种 就此灭绝 并不是所有小行星都这么大
Some of them are smaller. Here is one that came in over the United States in October of 1992. It came in on a Friday night. Why is that important? Because back then, video cameras were just starting to become popular, and parents would bring them to their kids' football games to film their kids playing football. And since this came in on a Friday, they were able to get this great footage of this thing breaking up as it came in over West Virginia, Maryland, Pennsylvania and New Jersey until it did that to a car in New York.
有些小行星或陨石体型较小 这是1992年10月 砸到美国的 一块陨石 那是一个星期五的晚上 这为什么值得一提 当时摄影机 才刚开始普及 人们都随身携带 家长们带着摄影机 去拍摄孩子的足球比赛 这颗陨石在一个周五从天而降 划过西弗吉尼亚州 马里兰州 宾夕法尼亚洲 新泽西州 一路解体 直到它砸在纽约州的一辆车上 人们就把这一壮景拍了下来
(Laughter)
(众人笑)
Now, this is not a 200-mile-wide crater, but then again, you can see the rock, which is sitting right here, about the size of a football, that hit that car and did that damage. Now, this thing was probably about the size of a school bus when it first came in. It broke up through atmospheric pressure, it crumbled, and then the pieces fell apart and did some damage. Now, you wouldn't want that falling on your foot or your head, because it would do that to it. That would be bad. But it won't wipe out, you know, all life on Earth, so that's fine.
它没有形成一个200英里宽的陨坑 但是你看那块陨石 落在地上 大概有一个橄榄球大小 能把那车砸成那样 这块陨石在刚进入大气层时 大概有一辆公共汽车那么大 它在大气层中摩擦燃烧 解体 碎片四散 造成了一些破坏 你可不想被这些家伙砸到脚或头 因为一被砸到 就糟糕了 但至少它不会毁灭
But it turns out, you don't need something six miles across to do a lot of damage. There is a median point between tiny rock and gigantic rock, and in fact, if any of you have ever been to near Winslow, Arizona, there is a crater in the desert there that is so iconic that it is actually called "Meteor Crater." To give you a sense of scale, this is about a mile wide. If you look up at the top, that's a parking lot, and those are recreational vehicles right there. So it's about a mile across, 600 feet deep. The object that formed this was probably about 30 to 50 yards across, so roughly the size of Macky Auditorium here. It came in at speeds that were tremendous, slammed into the ground, blew up, and exploded with the energy of roughly a 20-megaton nuclear bomb -- a very hefty bomb. This was 50,000 years ago, so it may have wiped out a few buffalo or antelope, or something like that out in the desert, but it probably would not have caused global devastation.
地球上所有的生命 所以问题不大 然而 即使是体型小于6英里宽的小行星陨石 也能造成巨大的破坏 在小石块和巨石之间 存在一个中间点 你们可能有人去过亚利桑那州的温斯洛 那里附近的沙漠里就有一个陨坑 这个著名的陨坑就叫做“陨石坑” 它大概有一英里宽 往上看 那是一个停车场 那些房车就停放在那里 它大约1英里宽 600英尺深 陨石的大小大概为 30到50码宽 大概有这个礼堂这么大 它的飞行速度极快 撞入地表 爆炸 释放的能量 相当于一枚20兆吨的核弹 一枚相当给力的炸弹 这发生在5万年前 当时可能也就消灭了 沙漠上的几头野牛或羚羊 可能不会造成
It turns out that these things don't have to hit the ground
全球性的灾难
to do a lot of damage. Now, in 1908, over Siberia, near the Tunguska region -- for those of you who are Dan Aykroyd fans and saw "Ghostbusters," when he talked about the greatest cross-dimensional rift since the Siberia blast of 1909, where he got the date wrong, but that's OK.
陨石即使没有砸到地面 也会造成巨大的破坏 1908年在西伯利亚 靠近通古斯卡河流域--大家可能有人 是Dan Aykroyd的粉丝 看过“捉鬼敢死队” 他谈到过1909年西伯利亚大爆炸后出现的大裂谷 他当时把时间说错了 不过没关系(众人笑)
(Laughter)
应该是1908年 没事儿 我可以忍受
It was 1908. That's fine. I can live with that.
(众人笑)
(Laughter)
Another rock came into the Earth's atmosphere and this one blew up above the ground, several miles up above the surface of the Earth. The heat from the explosion set fire to the forest below it, and then the shock wave came down and knocked down trees for hundreds of square miles. This did a huge amount of damage. And again, this was a rock probably roughly the size of this auditorium that we're sitting in. In Meteor Crater, it was made of metal, and metal is much tougher, so it made it to the ground. The one over Tunguska was probably made of rock, and that's much more crumbly, so it blew up in the air.
另一块陨石进入了大气层 在距地表几英里的地方 爆炸 爆炸产生的热 将下面的森林点燃 冲击波将几百平方英里的森林 夷为平地 这造成了巨大的破坏 这块陨石 大概有我们这个礼堂这么大 形成陨石坑的陨石由金属组成 金属较为坚固 因此最终到达了地面 经过通古斯上空的那颗陨石 可能是由石头组成的 比较脆
Either way, these are tremendous explosions -- 20 megatons. Now, when these things blow up, they're not going to do global ecological damage. They're not going to do something like the dinosaur killer did. They're just not big enough. But they will do global economic damage, because they don't have to hit, necessarily, to do this kind of damage. They don't have to do global devastation. If one of these things were to hit pretty much anywhere, it would cause a panic. But if it came over a city, an important city -- not that any city is more important than others, but some of them we depend on more on the global economic basis -- that could do a huge amount of damage to us as a civilization. So, now that I've scared the crap out of you --
所以在空中爆炸了 而这两颗陨石 都造成了20兆吨的巨大爆炸 这样的陨石爆炸 不会造成全球性的生态破坏 它们不会像灭绝恐龙的那颗小行星那样 造成如此严重的破坏 它们不够大 但它们可以造成全球性的经济破坏 因为它们即使不着地 也能造成这样的破坏 它们即使不造成全球性的灾难 也能达到破坏的效果 任何一颗陨石要是即将撞上地球 不管撞在哪里 都会引起恐慌 如果它经过一个城市 一个重要的城市 我不是说一个城市比其它城市重要 但是我们在全球经济层面上 更依赖某些城市 这会对我们的文明 造成巨大破坏
我把你们都吓趴下了吧
(Laughter)
(众人笑)
what can we do about this? This is a potential threat. Let me note that we have not had a giant impact like the dinosaur killer for 65 million years. They're very rare. The smaller ones happen more often, but probably on the order of a millennium, every few centuries or every few thousand years. But it's still something to be aware of. Well, what do we do about them? The first thing we have to do is find them. This is an image of an asteroid that passed us in 2009. It's right here. But you can see that it's extremely faint. I don't know if you can see that in the back row. These are just stars.
我们怎么办呢 这是个潜在的威胁 我提醒你们一下 我们已经有6500万年没有遭遇 灭绝恐龙的小行星造成的那种破坏了 这非常罕见 体积较小的小行星袭击地球的次数稍多一些 但也就一千年 几百年或几千年发生一次 但这还是值得引起注意 我们怎么对付它们 我们首先要把它们找出来 这是2009年 经过地球的一颗小行星 就在这里 可以看到 它非常暗 我都不确定坐在后排的观众能否看到 这些只是星星
This is a rock that was about 30 yards across, so roughly the size of the ones that blew up over Tunguska and hit Arizona 50,000 years ago. These things are faint. They're hard to see, and the sky is really big. We have to find these things first. Well, the good news is, we're looking for them. NASA has devoted money to this; the National Science Foundation and other countries are interested in doing this. We're building telescopes that are looking for the threat.
这是一颗直径约为30码的陨石 它的大小和在通古斯上空爆炸的小行星 以及5万年前砸到亚利桑那州的小行星差不多 这些行星都很暗 很难看清楚 天空实在太大了 我们必须先把它们找出来 好消息是 我们正在寻找这些小行星 美国国家航空航天局正在这上面投钱 美国国家科学基金 还有其它国家都有意这么做 我们正在建造望远镜来寻找可能的威胁
That's a great first step. But what's the second step? The second step is if we see one heading toward us, we have to stop it. What do we do? You've probably heard about the asteroid Apophis. If you haven't yet, you will. If you've heard about the Mayan 2012 apocalypse, you're going to hear about Apophis, because you're keyed in to all the doomsday networks, anyway.
这是意义非凡的第一步 那么第二步呢 第二步就是 当发现有一颗小行星向我们飞来 我们必须阻止它 怎么阻止 你们可能听说过一颗名叫 阿波菲斯的小行星 如果没听过 现在你就知道了 如果你听说过玛雅人的2012末日说 你就会听到阿波菲斯 因为你横竖都已经被
(Laughter)
关于世界末日的网罗给套牢了
Apophis is an asteroid that was discovered in 2004. It's roughly 250 [meters] across, so it's pretty big -- bigger than a football stadium. And it's going to pass by the Earth in April of 2029. And it's going to pass us so close that it's actually going to come underneath our weather satellites. The Earth's gravity is going to bend the orbit of this thing so much that if it's just right, if it passes through this region of space, this kidney-bean-shaped region called the keyhole, the Earth's gravity will bend it just enough that seven years later, on April 13 -- which is a Friday, I'll note -- in the year 2036 --
阿波菲斯是2004年被发现的一颗小行星 它的直径约为250码 可见它的个头可不小 它比一个足球场还大 它将于2029年4月飞过地球上空 它将非常接近地球 会从我们的气象卫星下面 飞过去 而地心引力会使它的运行轨道发生弯曲 如果这正好使它 穿过这个区域 这个蚕豆形状的区域 我们称钥匙眼 地心引力会使其轨道弯曲 这样它在七年之后 也就是2036年4月13日星期五这一天
(Laughter)
(众人笑)
you can't plan that kind of stuff --
这种事情可没法作安排
(Laughter)
阿波菲斯会在这天撞上地球
Apophis is going to hit us. And it's 250 meters across, so it would do unbelievable damage. The good news is that the odds of it actually passing through this keyhole and hitting us next go-around are one in a million, roughly -- very, very low odds. So I personally am not lying awake at night worrying about this at all. I don't think Apophis is a problem. In fact, Apophis is a blessing in disguise, because it woke us up to the dangers of these things. This thing was discovered just a few years ago and could hit us a few years from now. It won't, but it gives us a chance to study these kinds of asteroids.
它的直径为250码 后果将不堪设想 值得庆幸的是 它穿过这个钥匙眼 撞上地球的几率为百万分之一 几率非常非常低 反正我可不会为了它而辗转反侧睡不着 我们不需要太担心阿波菲斯 阿波菲斯其实是件好事 因为 它提醒了我们要注意 这些小行星的威胁 我们几年前发现了这颗小行星 它有可能在几年后与地球相撞 它不会撞上地球 但它让我们有机会
We didn't really necessarily understand these keyholes, and now we do, and it turns out that's really important, because how do you stop an asteroid like this? Well, let me ask you: What happens if you're standing in the road and a car's headed for you? What do you do? You do this. Right? Move, and the car goes past you. But we can't move the Earth, at least not easily, but we can move a small asteroid.
研究这些小行星 我们之前对这些钥匙眼并不了解 现在我们有所了解了 并知道其中的重大意义 要不我们如何阻止这样一颗小行星呢 我问你们 如果你站在路中间 一辆车朝你驶来 会有什么情况发生 你会怎么做 你会这么做 挪开 对吧 让车过去 但是 我们不能挪动地球 就算要挪也没那么容易 但我们挪开那颗小行星
And it turns out, we've even done it. In the year 2005, NASA launched a probe called Deep Impact, which slammed a piece of itself into the nucleus of a comet. Comets are very much like asteroids. The purpose wasn't to push it out of the way; the purpose was to make a crater to excavate the material and see what was underneath the surface of this comet, which we learned quite a bit about. We did move the comet a little tiny bit -- not very much, but that wasn't the point. However, think about this: This thing is orbiting the Sun at 10, 20 miles per second. We shot a space probe at it and hit it, OK? Imagine how hard that must be, and we did it. That means we can do it again. If we see an asteroid that's coming toward us, headed right for us, and we have two years to go? Boom! We hit it. You know, if you watch the movies --
其实 我们已经这么做过了 2005年 NASA发射了一个名为 "天地大冲撞"的探测器 探测器的一部分嵌入了一颗彗星的内核 彗星跟小行星十分相似 这么做目的不是为了把它推出轨道 而是为了制造一个陨坑 从彗星表面刨出一些物质 接着对物质 进行深入研究 我们的确将那颗彗星挪动了一点点 但这不是重点 但是 我们这样想 这个天体围绕着太阳 以每秒10英里 20英里的速度运行 我们把一个太空探测器发射过去并击中了它 想象一下 这有多困难 但我们做到了 这意味着 我们还能这么做 如果有必要 如果看到一颗小行星飞来 正朝着我们飞过来 我们还有两年的时间 砰!击中它 我们可以试试看 如果你看电影
(Laughter)
你可能会想
you might think: Why don't we use a nuclear weapon? Well, you can try that, but the problem is timing. Shoot a nuclear weapon at this thing, you have to blow it up within a few milliseconds of tolerance, or else you'll miss it. And there are a lot of other problems with that; it's very hard to do. But just hitting something? That's pretty easy. I think even NASA can do that, and proved that they can.
为什么我们不用核武器呢 你可以尝试用核武器 但是发射时间很成问题 对这样的天体发射核弹 你必须在几毫秒之内锁定目标 否则你就会脱靶 这里面有很多问题 操作相当困难 但想要打中一个物体 是轻而易举的 连NASA都办得到
(Laughter)
他们以实力证明了这一点 (众人笑)
The problem is, if you hit this asteroid, you've changed the orbit, you measure the orbit, then you find out, oh yeah, we just pushed it into a keyhole, and now it's going to hit us in three years. Well, my opinion is: fine! It's not hitting us in six months -- that's good.
问题是 如果击中了这颗小行星 它的轨道改变了 会发生什么情况 你测量了它的轨道 结果发现 呀 正好 我们把它推到钥匙眼里了 它三年后就要撞地球了 我以为 这也无妨 反正它不会在半年内撞上我们 这就行了
Now we have three years to do something else. And you can hit it again. That's kind of ham-fisted; you might just push it into a third keyhole or whatever, so you don't do that. And this is the part -- it's the part I just love.
我们有三年的时间来应对 你可以再打它一次 真是重拳出击啊 结果可能把它推进另一个钥匙眼 不太明智 这是我最喜欢的部分 (众人笑)
(Laughter)
我们先来硬的:“啊呀呀!砰!
After the big macho "Grr ... bam! We're gonna hit this thing in the face," then we bring in the velvet gloves.
我们给这个家伙当头一棒。" 接着再来软的
(Laughter)
(众人笑)
There's a group of scientists and engineers and astronauts, and they call themselves The B612 Foundation. For those of you who've read "The Little Prince," you understand that reference, I hope -- the little prince lived on an asteroid called B612. These are smart guys -- men and women -- astronauts, like I said, engineers. Rusty Schweickart, who was an Apollo 9 astronaut, is on this. Dan Durda, my friend who made this image, works here at Southwest Research Institute in Boulder, on Walnut Street. He created this image for this. He's actually one of the astronomers who works for them. If we see an asteroid that's going to hit the Earth and we have enough time, we can hit it to move it into a better orbit.
有这样一群科学家 工程师 和宇航员 他们称自己为 B612 Foundation组织 你们要是读过《小王子》这本书 就该明白这个名称的出处 小王子住在一颗小行星上 这颗行星就叫B612 这是一群聪明人 有男有女 宇航员 工程师 Rusty Schweickart 曾是阿波罗9号的宇航员 我的朋友Dan Durda 拍摄这张图片的人 现在在Walnut街的博尔德西南研究院工作 他拍摄了这张图片 他实际上是在这里工作的 天文学家之一 如果我们发现一颗小行星 即将撞击地球 我们有足够的时间 对它进行打击 把它推入一个更利于我们的轨道
But then what we do is launch a probe that has to weigh a ton or two. It doesn't have to be huge -- a couple of tons, not that big -- and you park it near the asteroid. You don't land on it, because these things are tumbling end over end. It's very hard to land on them. Instead you get near it. The gravity of the asteroid pulls on the probe, and the probe has a couple of tons of mass. It has a little tiny bit of gravity, but it's enough that it can pull the asteroid, and you have your rocket set up -- you can barely see it here, but there's rocket plumes -- and these guys are connected by their own gravity, and if you move the probe very slowly -- very, very gently, you can very easily finesse that rock into a safe orbit. You can even put in orbit around the Earth where we could mine it, although that's a whole other thing; I won't go into that.
我们要做的是将一个重一两吨的探测器发射出去 探测器体积不需太大 几吨重就行了 个头不大 你可以把它停在小行星旁边 不要把它降落在上面 因为这些天体不稳 很难在上面降落 因而要停在它近旁 小行星的引力会把探测器拉近 探测器有几吨的质量 探测器只有一点引力 但这足够 让它与小行星拉近 探测器上装有火箭 噢 你可能看不清楚 但上面确有火箭发射器 这些家伙都由引力连接在一起 如果你慢慢地 轻轻地移动探测器 你可以轻易地 把那颗小行星移入一个安全轨道 你甚至可以把它移到围绕地球的 一个轨道上以便把它炸掉 但这是另一回事了 我就不奔那儿去了
(Laughter)
(众人笑)
But we'd be rich!
但是 我们到时候就发财了
(Laughter)
(众人笑)
So think about this, right? There are these giant rocks flying out there, and they're hitting us, and they're doing damage to us. But we've figured out how to do this, and all the pieces are in place to do this. We have astronomers with telescopes, looking for them. We have very, very smart people, who are concerned about this and figuring out how to fix the problem, and we have the technology to do this. This probe actually can't use chemical rockets. Chemical rockets provide too much thrust, too much push. The probe would just shoot away.
设想一下 这些巨石在太空中飞来飞去 准备撞上地球 造成破坏 而我们已经找到办法 所有防御工作都落实到位了 我们有天文学家 各就各位 使用望远镜 寻找这些天体 我们有一群聪明人 非常非常聪明的人 他们关心这个问题 并想办法解决问题 我们还具备了相应的科技 这个探测器实际上不能使用化学火箭 化学火箭的助推力太强 会把探测器打飞
We invented something called an ion drive, which is a very, very, very low-thrust engine. It generates the force a piece of paper would have on your hand -- incredibly light, but it can run for months and years, providing that very gentle push. If anybody here is a fan of the original "Star Trek," they ran across an alien ship that had an ion drive, and Spock said, "They're very technically sophisticated. They're a hundred years ahead of us with this drive." Yeah, we have an ion drive now. We don't have the Enterprise, but we've got an ion drive now.
我们发明了离子助推器 这是个助推力非常低的引擎 它制造出的力 如同放在手上的一张纸 出奇地轻 但它能够经年累月地工作 制造这样一种轻柔的力 喜欢原版“星际迷航”(电影)的人应该知道 当他们碰到一架装有 离子助推器的外星飞船时Spock说: “这些仪器的技术含量太高了。 他们的助推器领先我们一百年。” 我们现在也有离子助推器啦 (众人笑) 我们还没有“进取号”飞船
(Laughter)
但我们有离子助推器
(Applause)
(众人鼓掌)
Spock.
Spock(电影人物名)
(Laughter) So ... That's the difference -- that's the difference between us and the dinosaurs. This happened to them. It doesn't have to happen to us. The difference between the dinosaurs and us is that we have a space program and we can vote, and so we can change our future.
(众人笑) 因此 这就是我们和恐龙之间的 不同之处 这是它们的结局 这样的结局不会发生在我们身上 我们和恐龙之间的不同 在于我们有太空项目 我们可以投选票 因此我们能够改变未来
(Laughter)
(众人笑)
We have the ability to change our future. Sixty-five million years from now, we don't have to have our bones collecting dust in a museum. Thank you very much.
我们有能力改变未来 6500万年之后 我们的骨头 不会被放在博物馆里接灰尘
(Applause)
非常感谢大家