TEDxBoulder 2011
Phil Plait: How to defend Earth from asteroids
菲尔·普莱特:天地大冲撞
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什么东西宽6英里并能在一瞬间毁灭一切文明? 答案是小行星。而在太空中，小行星的数量可不少。菲尔·普莱特用他的幽默和生动的描绘让TEDxBoulder的观众领略了小行星的杀伤力，并告诉我们应采取哪些必要的措施进行防御。
Phil Plait - Astronomer
Phil Plait blogs at Bad Astronomy, where he deconstructs misconceptions and explores the wonder of the universe. Full bio
Phil Plait blogs at Bad Astronomy, where he deconstructs misconceptions and explores the wonder of the universe. Full bio
Double-click the English transcript below to play the video.
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I want to talk to you about something
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我想和大家探讨一样东西
00:18
kind of big.
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一个庞然大物
00:21
We'll start here.
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我们先从这里讲起
00:24
65 million years ago
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6500万年前
00:27
the dinosaurs had a bad day.
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恐龙们倒了大霉了
00:30
(Laughter)
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（众人笑）
00:33
A chunk of rock six miles across,
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一块长达6英里的巨石
00:36
moving something like 50 times
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以出膛子弹50倍的速度
00:38
the speed of a rifle bullet,
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向前运行
00:40
slammed into the Earth.
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当头撞上了地球
00:42
It released its energy all at once,
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一时间 它释放出了所有能量
00:44
and it was an explosion that was
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爆炸所产生的威力
00:46
mind-numbing.
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令人无法想象
00:48
If you took every nuclear weapon ever built
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如果将冷战最紧张时期
00:50
at the height of the Cold War,
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所有核武器
00:52
lumped them together and blew them up
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堆成一堆
00:54
at the same time,
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再同时引爆
00:56
that would be one one-millionth
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所产生的威力
00:58
of the energy released at that moment.
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充其量还只是其百万分之一
01:02
The dinosaurs had a really bad day.
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恐龙们真是倒了大霉了
01:05
Okay?
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对吧
01:07
Now, a six-mile-wide rock is very large.
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一块6英里宽的巨石非常大
01:09
We all live here in Boulder.
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我们都住在Boulder市
01:11
If you look out your window and you can see
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从窗外看去 你可以看见
01:13
Long's Peak, you're probably familiar with it.
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朗斯峰 你们对这山都不陌生吧
01:15
Now, scoop up Long's Peak, and put it out
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把朗斯峰连锅端起来
01:17
in space.
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把它放到外太空
01:19
Take Meeker, Mt. Meeker. Lump that in there,
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把米克山也拔起来
01:21
and put that in space as well,
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放到外太空去
01:23
and Mt. Everest, and K2,
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再加上珠穆朗玛峰 乔戈里峰
01:25
and the Indian peaks.
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印第安山脉群峰
01:27
Then you're starting to get an idea of
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现在你们应该可以想象
01:29
how much rock we're talking about, okay?
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这块巨石有多大了吧
01:31
We know it was that big because of
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我们从爆炸释放的威力和之后留下的陨坑
01:33
the impact it had and the crater it left.
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得知这块巨石的确有这么大
01:35
It hit in what we now know as Yucatan,
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它所撞击的地点
01:37
the Gulf of Mexico.
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是现位于墨西哥湾的尤卡坦
01:39
You can see here, there's the
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你可以看这里
01:41
Yucatan Peninsula, if you recognize Cozumel
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如果你认得东海岸的科祖梅尔岛
01:43
off the east coast there.
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这里就是尤卡坦半岛
01:45
Here is how big of a crater was left.
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留下的陨坑有这么大
01:48
It was huge. To give you a sense of the scale,
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它非常大 你可以估计一下它的大小
01:50
okay, there you go. The scale here is
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你看
01:52
50 miles on top, a hundred kilometers
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它上面宽50英里
01:54
on the bottom. This thing was
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下面宽100公里
01:56
300 kilometers across -- 200 miles --
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跨度为300公里 也就是200英里
01:58
an enormous crater that excavated out
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这个巨大的陨坑
02:00
vast amounts of earth that splashed around
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把大量泥土掘起 抛散开来 尘土弥漫
02:03
the globe and set fires all over the planet,
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整个地球四处起火
02:06
threw up enough dust to block out the sun.
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烟尘遮盖了阳光
02:09
It wiped out 75 percent of all species
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地球上75%的物种
02:11
on Earth.
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就此灭绝
02:13
Now, not all asteroids are that big.
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并不是所有小行星都这么大
02:16
Some of them are smaller.
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有些小行星或陨石体型较小
02:18
Here is one that came in
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这是1992年10月
02:21
over the United States
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砸到美国的
02:23
in October of 1992.
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一块陨石
02:25
It came in on a Friday night.
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那是一个星期五的晚上
02:27
Why is that important?
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这为什么值得一提
02:29
Because back then, video cameras were
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当时摄影机
02:31
just starting to become popular, and people
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才刚开始普及
02:33
would bring them, parents would bring them,
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人们都随身携带 家长们带着摄影机
02:35
to their kids' football games to film their kids
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去拍摄孩子的足球比赛
02:37
play football. And since this came in on a Friday,
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这颗陨石在一个周五从天而降
02:40
they were able to get this great footage
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划过西弗吉尼亚州 马里兰州
02:42
of this thing breaking up as it came in
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宾夕法尼亚洲 新泽西州
02:44
over West Virgina, Maryland, Pennsylvania
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一路解体
02:46
and New Jersey until it did that
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直到它砸在纽约州的一辆车上
02:48
to a car in New York.
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人们就把这一壮景拍了下来
02:50
(Laughter)
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（众人笑）
02:52
Now, this is not a 200-mile-wide crater,
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它没有形成一个200英里宽的陨坑
02:55
but then again you can see the rock
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但是你看那块陨石
02:57
which is sitting right here,
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落在地上
02:59
about the size of a football, that hit
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大概有一个橄榄球大小
03:01
that car and did that damage.
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能把那车砸成那样
03:03
Now this thing was probably about the size
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这块陨石在刚进入大气层时
03:05
of a school bus when it first came in.
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大概有一辆公共汽车那么大
03:07
It broke up through atmospheric pressure,
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它在大气层中摩擦燃烧
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it crumbled, and then the pieces fell apart
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解体 碎片四散
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and did some damage.
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造成了一些破坏
03:13
Now, you wouldn't want that falling on your foot
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你可不想被这些家伙砸到脚或头
03:15
or your head, because it would do that to it.
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因为一被砸到
03:17
That would be bad.
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就糟糕了
03:19
But it won't wipe out, you know, all life
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但至少它不会毁灭
03:21
on Earth, so that's fine. But it turns out,
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地球上所有的生命 所以问题不大
03:23
you don't need something six miles across
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然而 即使是体型小于6英里宽的小行星陨石
03:26
to do a lot of damage.
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也能造成巨大的破坏
03:28
There is a median point between tiny rock
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在小石块和巨石之间
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and gigantic rock, and in fact, if any of you
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存在一个中间点
03:32
have ever been to near Winslow, Arizona,
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你们可能有人去过亚利桑那州的温斯洛
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there is a crater in the desert there that is
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那里附近的沙漠里就有一个陨坑
03:38
so iconic that it is actually called Meteor Crater.
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这个著名的陨坑就叫做“陨石坑”
03:42
To give you a sense of scale, this is about a mile wide.
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它大概有一英里宽
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If you look up at the top, that's a parking lot,
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往上看 那是一个停车场
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and those are recreational vehicles right there.
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那些房车就停放在那里
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So it's about a mile across, 600 feet deep.
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它大约1英里宽 600英尺深
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The object that formed this was probably about
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陨石的大小大概为
03:57
30 to 50 yards across, so roughly the size
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30到50码宽
04:00
of Mackey Auditorium here.
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大概有这个礼堂这么大
04:03
It came in at speeds that were tremendous,
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它的飞行速度极快
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slammed into the ground, blew up,
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撞入地表 爆炸
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and exploded with the energy of roughly
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释放的能量
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a 20-megaton nuclear bomb --
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相当于一枚20兆吨的核弹
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a very hefty bomb.
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一枚相当给力的炸弹
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This was 50,000 years ago, so it may have
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这发生在5万年前
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wiped out a few buffalo or antelope,
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当时可能也就消灭了
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or something like that out in the desert,
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沙漠上的几头野牛或羚羊
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but it probably would not have caused
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可能不会造成
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global devastation.
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全球性的灾难
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It turns out that these things don't have to
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陨石即使没有砸到地面
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hit the ground to do a lot of damage.
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也会造成巨大的破坏
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Now, in 1908, over Siberia, near the
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1908年在西伯利亚
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Tunguska region -- for those of you who are
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靠近通古斯卡河流域--大家可能有人
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Dan Aykroyd fans and saw "Ghostbusters,"
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是Dan Aykroyd的粉丝 看过“捉鬼敢死队”
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when he talked about the greatest cross-dimensional rift
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他谈到过1909年西伯利亚大爆炸后出现的大裂谷
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since the Siberia blast of 1909, where he got
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他当时把时间说错了
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the date wrong, but that's okay. (Laughter)
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不过没关系（众人笑）
04:44
It was 1908. That's fine. I can live with that.
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应该是1908年 没事儿 我可以忍受
04:47
(Laughter)
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（众人笑）
04:50
Another rock came into the Earth's atmosphere
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另一块陨石进入了大气层
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and this one blew up above the ground, several
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在距地表几英里的地方
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miles up above the surface of the Earth.
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爆炸
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The heat from the explosion set fire to the
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爆炸产生的热
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forest below it, and then the shock wave
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将下面的森林点燃
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came down and knocked down trees for
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冲击波将几百平方英里的森林
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hundreds of square miles, okay?
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夷为平地
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This did a huge amount of damage.
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这造成了巨大的破坏
05:11
And again, this was a rock probably roughly
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这块陨石
05:13
the size of this auditorium that we're sitting in.
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大概有我们这个礼堂这么大
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In Meteor Crater it was made of metal,
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形成陨石坑的陨石由金属组成
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and metal is much tougher, so it made it
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金属较为坚固
05:19
to the ground.
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因此最终到达了地面
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The one over Tunguska was probably made
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经过通古斯上空的那颗陨石
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of rock, and that's much more crumbly, so it
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可能是由石头组成的 比较脆
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blew up in the air. Either way, these are
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所以在空中爆炸了 而这两颗陨石
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tremendous explosions, 20 megatons.
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都造成了20兆吨的巨大爆炸
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Now, when these things blow up, they're not
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这样的陨石爆炸
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going to do global ecological damage.
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不会造成全球性的生态破坏
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They're not going to do something like
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它们不会像灭绝恐龙的那颗小行星那样
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the dinosaur-killer did.
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造成如此严重的破坏
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They're just not big enough.
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它们不够大
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But they will do global economic damage,
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但它们可以造成全球性的经济破坏
05:43
because they don't have to hit, necessarily,
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因为它们即使不着地
05:45
to do this kind of damage.
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也能造成这样的破坏
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They don't have to do global devastation.
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它们即使不造成全球性的灾难 也能达到破坏的效果
05:49
If one of these things were to hit
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任何一颗陨石要是即将撞上地球
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pretty much anywhere, it would cause a panic.
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不管撞在哪里 都会引起恐慌
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But if it came over a city, an important city --
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如果它经过一个城市 一个重要的城市
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not that any city is more important than others,
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我不是说一个城市比其它城市重要
05:57
but some of them we depend on them more
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但是我们在全球经济层面上
05:59
on the global economic basis -- that could do
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更依赖某些城市
06:02
a huge amount of damage to us
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这会对我们的文明
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as a civilization.
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造成巨大破坏
06:07
So, now that I've scared the crap out of you ...
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我把你们都吓趴下了吧
06:10
(Laughter)
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（众人笑）
06:12
what can we do about this? All right?
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我们怎么办呢
06:14
This is a potential threat.
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这是个潜在的威胁
06:16
Let me note that we have not had
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我提醒你们一下
06:18
a giant impact like the dinosaur-killer
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我们已经有6500万年没有遭遇
06:20
for 65 million years. They're very rare.
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灭绝恐龙的小行星造成的那种破坏了 这非常罕见
06:23
The smaller ones happen more often, but
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体积较小的小行星袭击地球的次数稍多一些
06:26
probably on the order of a millennium,
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但也就一千年
06:28
every few centuries or every few thousand
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几百年或几千年发生一次
06:30
years, but it's still something to be aware of.
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但这还是值得引起注意
06:33
Well, what do we do about them?
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我们怎么对付它们
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The first thing we have to do is find them.
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我们首先要把它们找出来
06:37
This is an image of an asteroid that passed
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这是2009年
06:39
us in 2009.
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经过地球的一颗小行星
06:41
It's right here.
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就在这里
06:43
But you can see that it's extremely faint.
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可以看到 它非常暗
06:45
I don't even know if you can see that
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我都不确定坐在后排的观众能否看到
06:47
in the back row. These are just stars.
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这些只是星星
06:49
This is a rock that was about 30 yards across,
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这是一颗直径约为30码的陨石
06:51
so roughly the size of the ones that blew up
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它的大小和在通古斯上空爆炸的小行星
06:53
over Tunguska and hit Arizona 50,000 years ago.
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以及5万年前砸到亚利桑那州的小行星差不多
06:56
These things are faint.
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这些行星都很暗
06:58
They're hard to see, and the sky is really big.
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很难看清楚 天空实在太大了
07:00
We have to find these things first.
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我们必须先把它们找出来
07:02
Well the good news is, we're looking for them.
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好消息是 我们正在寻找这些小行星
07:04
NASA has devoted money to this.
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美国国家航空航天局正在这上面投钱
07:06
The National Science Foundation, other
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美国国家科学基金
07:08
countries are very interested in doing this.
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还有其它国家都有意这么做
07:10
We're building telescopes that are looking
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我们正在建造望远镜来寻找可能的威胁
07:12
for the threat. That's a great first step,
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这是意义非凡的第一步
07:14
but what's the second step? The second step
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那么第二步呢
07:16
is that we see one heading toward us,
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第二步就是 当发现有一颗小行星向我们飞来
07:18
we have to stop it. What do we do?
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我们必须阻止它 怎么阻止
07:20
You've probably heard about the asteroid
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你们可能听说过一颗名叫
07:22
Apophis. If you haven't yet, you will.
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阿波菲斯的小行星 如果没听过 现在你就知道了
07:25
If you've heard about the Mayan 2012
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如果你听说过玛雅人的2012末日说
07:27
apocalypse, you're going to hear about Apophis,
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你就会听到阿波菲斯
07:29
because you're keyed in to all the doomsday
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因为你横竖都已经被
07:31
networks anyway.
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关于世界末日的网罗给套牢了
07:34
Apophis is an asteroid that was discovered in 2004.
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阿波菲斯是2004年被发现的一颗小行星
07:37
It's roughly 250 yards across, so it's
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它的直径约为250码
07:40
pretty big -- big size, you know,
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可见它的个头可不小
07:42
bigger than a football stadium -- and it's going to
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它比一个足球场还大
07:44
pass by the Earth in April of 2029.
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它将于2029年4月飞过地球上空
07:47
And it's going to pass us so close that it's
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它将非常接近地球
07:49
actually going to come underneath
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会从我们的气象卫星下面
07:51
our weather satellites.
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飞过去
07:53
The Earth's gravity is going to bend the orbit
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而地心引力会使它的运行轨道发生弯曲
07:55
of this thing so much that if it's just right,
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如果这正好使它
07:58
if it passes through this region of space,
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穿过这个区域
08:01
this kidney bean-shaped region called
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这个蚕豆形状的区域
08:03
the keyhole, the Earth's gravity will bend it
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我们称钥匙眼 地心引力会使其轨道弯曲
08:05
just enough that seven years later
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这样它在七年之后
08:07
on April 13, which is a Friday, I'll note,
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也就是2036年4月13日星期五这一天
08:09
in the year 2036 ... (Laughter)
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（众人笑）
08:12
-- you can't plan that kind of stuff --
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这种事情可没法作安排
08:15
Apophis is going to hit us. And it's
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阿波菲斯会在这天撞上地球
08:17
250 meters across, so it would do
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它的直径为250码
08:19
unbelievable damage.
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后果将不堪设想
08:21
Now the good news is that the odds of it
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值得庆幸的是
08:23
actually passing through this keyhole and
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它穿过这个钥匙眼
08:25
hitting us next go-around are one in a million,
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撞上地球的几率为百万分之一
08:27
roughly -- very, very low odds, so I personally
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几率非常非常低
08:29
am not lying awake at night worrying about this at all.
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反正我可不会为了它而辗转反侧睡不着
08:31
I don't think Apophis is a problem.
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我们不需要太担心阿波菲斯
08:33
In fact, Apophis is a blessing in disguise,
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阿波菲斯其实是件好事
08:35
because it woke us up to the dangers
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因为 它提醒了我们要注意
08:37
of these things.
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这些小行星的威胁
08:39
This thing was discovered just a few years
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我们几年前发现了这颗小行星
08:41
ago and could hit us a few years from now.
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它有可能在几年后与地球相撞
08:43
It won't, but it gives us a chance to study
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它不会撞上地球 但它让我们有机会
08:45
these kinds of asteroids. We didn't really
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研究这些小行星
08:47
necessarily understand these keyholes, and
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我们之前对这些钥匙眼并不了解
08:49
now we do and it turns out
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现在我们有所了解了
08:51
that's really important, because how do you
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并知道其中的重大意义
08:53
stop an asteroid like this?
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要不我们如何阻止这样一颗小行星呢
08:55
Well, let me ask you, what happens if you're
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我问你们 如果你站在路中间
08:57
standing in the middle of the road and a car's
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一辆车朝你驶来 会有什么情况发生
08:59
headed for you? What do you do? You do this.
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你会怎么做 你会这么做
09:01
Right? Move. The car goes past you.
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挪开 对吧 让车过去
09:03
But we can't move the Earth, at least
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但是 我们不能挪动地球
09:05
not easily, but we can move a small asteroid.
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就算要挪也没那么容易 但我们挪开那颗小行星
09:07
And it turns out, we've even done it.
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其实 我们已经这么做过了
09:09
In the year 2005, NASA launched a probe
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2005年 NASA发射了一个名为
09:12
called Deep Impact, which slammed into --
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"天地大冲撞"的探测器
09:15
slammed a piece of itself into the nucleus of a comet.
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探测器的一部分嵌入了一颗彗星的内核
09:18
Comets are very much like asteroids.
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彗星跟小行星十分相似
09:20
The purpose wasn't to push it out of the way.
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这么做目的不是为了把它推出轨道
09:22
The purpose was to make a crater to excavate
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而是为了制造一个陨坑
09:24
the material and see what was underneath
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从彗星表面刨出一些物质
09:26
the surface of this comet, which we learned
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接着对物质
09:28
quite a bit about.
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进行深入研究
09:30
We did move the comet a little tiny bit,
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我们的确将那颗彗星挪动了一点点
09:32
not very much, but that wasn't the point.
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但这不是重点
09:34
However, think about this.
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但是 我们这样想
09:36
This thing is orbiting the sun at
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这个天体围绕着太阳
09:38
10 miles per second, 20 miles per second.
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以每秒10英里 20英里的速度运行
09:40
We shot a space probe at it and hit it. Okay?
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我们把一个太空探测器发射过去并击中了它
09:42
Imagine how hard that must be, and we did it.
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想象一下 这有多困难 但我们做到了
09:45
That means we can do it again.
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这意味着 我们还能这么做
09:48
If we need, if we see an asteroid that's coming
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如果有必要 如果看到一颗小行星飞来
09:50
toward us, and it's headed right for us,
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正朝着我们飞过来
09:52
and we have two years to go, boom! We hit it.
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我们还有两年的时间 砰！击中它
09:55
You can try to -- you know, if you watch
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我们可以试试看 如果你看电影
09:57
the movies, you might think about,
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你可能会想
09:59
why don't we use a nuclear weapon?
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为什么我们不用核武器呢
10:01
It's like, well, you can try that, but the problem is timing.
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你可以尝试用核武器 但是发射时间很成问题
10:03
You shoot a nuclear weapon at this thing,
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对这样的天体发射核弹
10:05
you have to blow it up within a few milliseconds
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你必须在几毫秒之内锁定目标
10:07
of tolerance or else you'll just miss it.
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否则你就会脱靶
10:09
And there are a lot of other problems
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这里面有很多问题
10:11
with that. It's very hard to do.
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操作相当困难
10:13
But just hitting something? That's pretty easy.
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但想要打中一个物体 是轻而易举的
10:15
I think even NASA can do that,
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连NASA都办得到
10:17
and they proved that they can. (Laughter)
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他们以实力证明了这一点 （众人笑）
10:19
The problem is, what happens if you hit
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问题是 如果击中了这颗小行星
10:21
this asteroid, you've changed the orbit,
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它的轨道改变了 会发生什么情况
10:23
you measure the orbit and then you find out,
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你测量了它的轨道 结果发现
10:25
oh, yeah, we just pushed it into a keyhole,
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呀 正好 我们把它推到钥匙眼里了
10:27
and now it's going to hit us in three years.
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它三年后就要撞地球了
10:29
Well, my opinion is, fine. Okay?
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我以为 这也无妨
10:31
It's not hitting us in six months. That's good.
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反正它不会在半年内撞上我们 这就行了
10:33
Now we have three years to do something else.
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我们有三年的时间来应对
10:36
And you can hit it again. That's kind of
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你可以再打它一次
10:38
ham-fisted. You might just push it into a third
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真是重拳出击啊 结果可能把它推进另一个钥匙眼
10:40
keyhole or whatever, so you don't do that.
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不太明智
10:42
And this is the part, it's the part I just love.
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这是我最喜欢的部分
10:46
(Laughter)
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（众人笑）
10:48
After the big macho "Rrrrrrr BAM! We're
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我们先来硬的：“啊呀呀！砰！
10:50
gonna hit this thing in the face,"
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我们给这个家伙当头一棒。"
10:52
then we bring in the velvet gloves.
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接着再来软的
10:55
(Laughter)
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（众人笑）
10:58
There's a group of scientists and engineers
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有这样一群科学家 工程师
11:00
and astronauts and they call themselves
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和宇航员 他们称自己为
11:02
The B612 Foundation. For those of you
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B612 Foundation组织
11:04
who've read "The Little Prince,"
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你们要是读过《小王子》这本书
11:06
you understand that reference, I hope. The little prince
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就该明白这个名称的出处
11:08
who lived on an asteroid, it was called B612.
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小王子住在一颗小行星上 这颗行星就叫B612
11:10
These are smart guys -- men and women --
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这是一群聪明人 有男有女
11:12
astronauts, like I said, engineers.
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宇航员 工程师
11:14
Rusty Schweickart, who was an Apollo 9
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Rusty Schweickart 曾是阿波罗9号的宇航员
11:16
astronaut, is on this. Dan Durda, my friend
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我的朋友Dan Durda
11:18
who made this image, works here at
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拍摄这张图片的人
11:20
Southwest Research Institute in Boulder,
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现在在Walnut街的博尔德西南研究院工作
11:22
on Walnut Street. He created this image for this,
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他拍摄了这张图片
11:24
and he's actually one of the astronomers
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他实际上是在这里工作的
11:26
who works for them. If we see an asteroid
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天文学家之一 如果我们发现一颗小行星
11:28
that's going to hit the Earth and we have
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即将撞击地球
11:30
enough time, we can hit it to move it into
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我们有足够的时间 对它进行打击
11:33
a better orbit. But then what we do is we launch
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把它推入一个更利于我们的轨道
11:36
a probe that has to weigh a ton or two.
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我们要做的是将一个重一两吨的探测器发射出去
11:38
It doesn't have to be huge -- couple of tons,
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探测器体积不需太大 几吨重就行了
11:41
not that big -- and you park it near the asteroid.
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个头不大 你可以把它停在小行星旁边
11:44
You don't land on it, because these things are
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不要把它降落在上面
11:46
tumbling end over end. It's very hard to land on them.
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因为这些天体不稳 很难在上面降落
11:48
Instead you get near it.
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因而要停在它近旁
11:50
The gravity of the asteroid pulls on the probe,
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小行星的引力会把探测器拉近
11:52
and the probe has a couple of tons of mass.
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探测器有几吨的质量
11:55
It has a little tiny bit of gravity, but it's enough
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探测器只有一点引力 但这足够
11:57
that it can pull the asteroid, and you have your
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让它与小行星拉近
11:59
rockets set up, so you can -- oh, you can barely
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探测器上装有火箭 噢 你可能看不清楚
12:01
see it here, but there's rocket plumes -- and you
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但上面确有火箭发射器
12:03
basically, these guys are connected by their
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这些家伙都由引力连接在一起
12:05
own gravity, and if you move the probe very
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如果你慢慢地 轻轻地移动探测器
12:08
slowly, very, very gently, you can very easily
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你可以轻易地
12:12
finesse that rock into a safe orbit.
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把那颗小行星移入一个安全轨道
12:15
You can even put in orbit around the Earth
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你甚至可以把它移到围绕地球的
12:17
where we could mine it, although that's a
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一个轨道上以便把它炸掉
12:19
whole other thing. I won't go into that.
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但这是另一回事了 我就不奔那儿去了
12:21
(Laughter)
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（众人笑）
12:23
But we'd be rich!
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但是 我们到时候就发财了
12:25
(Laughter)
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（众人笑）
12:30
So think about this, right?
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设想一下
12:32
There are these giant rocks flying out there,
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这些巨石在太空中飞来飞去
12:34
and they're hitting us, and they're doing
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准备撞上地球
12:36
damage to us, but we've figured out how to do
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造成破坏 而我们已经找到办法
12:38
this, and all the pieces are in place to do this.
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所有防御工作都落实到位了
12:41
We have astronomers in place with telescopes
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我们有天文学家 各就各位 使用望远镜
12:43
looking for them. We have smart people,
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寻找这些天体 我们有一群聪明人
12:45
very, very smart people, who are concerned
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非常非常聪明的人 他们关心这个问题
12:47
about this and figuring out how to fix the
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并想办法解决问题
12:49
problem, and we have the technology to do this.
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我们还具备了相应的科技
12:52
This probe actually can't use chemical rockets.
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这个探测器实际上不能使用化学火箭
12:54
Chemical rockets provide too much thrust, too
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化学火箭的助推力太强
12:56
much push. The probe would just shoot away.
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会把探测器打飞
12:58
We invented something called an ion drive,
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我们发明了离子助推器
13:00
which is a very, very, very low-thrust engine.
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这是个助推力非常低的引擎
13:03
It generates the force a piece of paper would
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它制造出的力
13:05
have on your hand, incredibly light,
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如同放在手上的一张纸 出奇地轻
13:07
but it can run for months and years,
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但它能够经年累月地工作
13:10
providing that very gentle push.
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制造这样一种轻柔的力
13:13
If anybody here is a fan of the original "Star Trek,"
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喜欢原版“星际迷航”（电影）的人应该知道
13:15
they ran across an alien ship that had
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当他们碰到一架装有
13:17
an ion drive, and Spock said,
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离子助推器的外星飞船时Spock说：
13:19
"They're very technically sophisticated.
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“这些仪器的技术含量太高了。
13:21
They're a hundred years ahead of us with this drive."
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他们的助推器领先我们一百年。”
13:23
Yeah, we have an ion drive now. (Laughter)
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我们现在也有离子助推器啦 （众人笑）
13:25
We don't have the Enterprise, but
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我们还没有“进取号”飞船
13:27
we've got an ion drive now.
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但我们有离子助推器
13:29
(Applause)
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（众人鼓掌）
13:32
Spock.
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Spock（电影人物名）
13:34
(Laughter)
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（众人笑）
13:37
So ...
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因此
13:39
that's the difference, that's the difference
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这就是我们和恐龙之间的
13:41
between us and the dinosaurs.
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不同之处
13:43
This happened to them.
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这是它们的结局
13:45
It doesn't have to happen to us.
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这样的结局不会发生在我们身上
13:47
The difference between the dinosaurs and us
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我们和恐龙之间的不同
13:50
is that we have a space program
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在于我们有太空项目
13:52
and we can vote,
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我们可以投选票
13:54
and so we can change our future.
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因此我们能够改变未来
13:57
(Laughter)
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（众人笑）
13:58
We have the ability to change our future.
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我们有能力改变未来
14:01
65 million years from now,
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6500万年之后
14:03
we don't have to have our bones
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我们的骨头
14:05
collecting dust in a museum.
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不会被放在博物馆里接灰尘
14:07
Thank you very much.
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非常感谢大家
14:09
(Applause)
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（众人鼓掌）
ABOUT THE SPEAKER
Phil Plait - AstronomerPhil Plait blogs at Bad Astronomy, where he deconstructs misconceptions and explores the wonder of the universe.
Why you should listen
Phil Plait is the Bad Astronomer. Not a bad astronomer, but a blogger for Slate who debunks myths and misconceptions about astronomy -- and also writes about the beauty, wonder and importance of fundamental research.
He worked for six years on the Hubble Space Telescope, and directed public outreach for the Fermi Gamma-ray Space Telescope. He is a past president of the James Randi Educational Foundation, and was the host of Phil Plait's Bad Universe, a documentary series on the Discovery Channel.
Read more from Phil Plait in the Huffington Post's special TEDWeekends feature, "Asteroids: Getting Ready" >>
Phil Plait | Speaker | TED.com