星穹研习会02期——「畅想银河」

如果是第一次来，按"Ctrl+D"可以收藏随时查看更新~觉得WIKI好玩的话，请推荐给朋友哦～(◕ω＜)☆
按右上角“WIKI功能→编辑”即可修改页面内容。

宇宙中有无数的星球，无尽的故事，无限的可能。即便仍被重力束缚，人类对未知的畅想永远不会停歇。

主题

天文物理学中，行星形态的探究与地外生命的探索；以及对天文学的科普

嘉宾

迪迪尔•奎罗兹：瑞士天文学家，剑桥大学、苏黎世联邦理工学院教授，2019年诺贝尔物理学奖获得者。
在日内瓦大学读博士时，他和米歇尔•麦耶共同发现了围绕主序星的首颗太阳系外行星。奎洛兹用径向速度测量的方法分析了飞马座51，结果发现了一颗轨道周期为4.2天的行星。这颗行星就是飞马座51b，挑战了当时正统的关于行星形成的见解。

视频

观看视频

折叠

正文

We have to face a reality nobody would have imagined, not even the best sci-fi movie, the diversity of the planetary system that we have detected.
So the reality is way more diverse than anything we had in mind.
We have this lava planet, this frozen planet, this super Earth, mini Nepture.
This is the reality of the diversity of the planetary formation.
我们必须面对这样一个现实：即使最好的科幻电影，也无法展现行星系统的多样性。
现实总是远超我们的想象。
熔岩星球、冰雪星球、巨型地球、微缩版海王星……真实的行星形态各异，复杂多样。

In the 90s for the first time we demonstrated, using a new technique, that there are planet orbiting other stars. We found a planet orbiting a star called 51 Pegasi.
That planet was about the mass of Jupiter, similar to our own planet Jupiter, but had a very short orbit, was essentially very close to the star and then extremely hot.
This is what we call the Hot Jupiter and it was the beginning of a long series of discoveries, and what we call right now, the exoplanet revolution.
上世纪90年代，我们利用一种全新的技术，首次发现了一颗绕着其他恒星公转的行星。那是一颗围绕恒星「51 Pegasi」运行的系外行星。
这颗行星的质量与木星相近，虽然它跟木星很相似，但它的公转轨道很短，离恒星很近，所以这颗行星非常炽热。
也就是说，它属于所谓的「热木星」。以这颗行星为起点，我们迎来了一系列的新发现，就是现在我们所说的「系外行星革命」。

My name is Didier Queloz, I'm a professor of physics at Cambridge University and ETH Zurich.
My main activity is to study planets orbiting other stars, try to understand how they look like, and eventually trying to find out whether there may be some planet with life as well.
我是Didier Queloz，我在剑桥大学和苏黎世联邦理工学院担任物理学教授。
我的主要课题是：研究环绕其他恒星运转的行星，探究这些行星的构成，然后试着在这些行星上找寻可能存在的生命。

Science is everywhere in the society, and we should take any opportunity to bring science into life of everybody.
When you have people interested by video games. If there is a little bit of a chance that through this video games, through this exercise of the gaming and then I can sneak in and with a couple of minutes of interaction through the video games, I can maybe suggest some idea which is scientifically relevant, bring a little bit more knowledge into the society.
科学在当今社会中无处不在，所以我们需要抓住一切机会，让每个人都能了解科学。
电子游戏受到很多人的关注，我也希望能够通过游戏作为媒介，用几分钟的时间，借由此引入一些科学概念，并向玩家揭示一些科学知识，为整个社会的科普工作做一点微小的贡献。

Something which is great when you deal with what's called planetary science, is you can essentially expect everything.
We have learned in the past 30 years that the diversity of the planet are way more, and way larger than the one we experience on the solar system.
深入了解所谓的行星科学之后，你会发现，它最有趣的地方在于，宇宙中有无限可能。
过去30年来，我们发现，宇宙里行星的多样性，远远超过了太阳系中的行星们。

And assuming that there are so many planets and so many stars in the universe, it's very likely that there exist plenty of planets like they created for the game.
Jarilo-VI is the first planet you meet in Honkai: Star Rail. Covered by harsh hurricanes and snow, the planet has been covered by snow for hundreds of years. Snow almost killed the civilization there. And people on the planet somehow managed to maintain only one city with the help of a special energy.
When you talk about planet that is frosted and we know, that in the past of the earth we may have encountered this very special situation where the Earth was like a snowball.
宇宙里有无数形态各异的天体，游戏中所创造的行星很可能真实存在宇宙中。
雅利洛-Ⅵ是《崩坏：星穹铁道》中出现的第一颗行星，这颗行星时刻遭受着暴风雪的洗礼。几百年来一直被厚重的积雪所覆盖，冰雪几乎扼杀了这颗行星上的文明，只有一座城市依靠某种特殊的能源幸存了下来。
提到冰雪星球，我们很容易联想到，地球在漫长的演变过程中，也经历过类似的极端气候，被冰雪完全覆盖，变成一颗「雪球」。

When you're dealing with a frozen planet, there's a lot of possibilities.
First you have to realise that the gas, if you cool it down enough, like carbon dioxide, will become icy and frost.
So it's easy to consider a planet that will be seen as the gaseous planet, I mean cooling down enough and and looking very, very icy.
Now it depends also on the amount of water you have on the planet. Whether you have a big oceans and whether you want to create a kind of ice crust from this water or you don't have water at all, but you build up the kind of icy structure for all the tiny gas, that is transforming to solid because it's very cold.
So what matter here is the temperature. You have to cool down the temperature, so you should not get too close to the star. If you're too close to the star, it doesn't work.
讨论及此，其实需要考虑多种可能性。
首先我们要知道，二氧化碳等气体冷却到一定程度时，就会结冰结霜。
我们不妨把这样一个星球看作是「气态星球」。由于温度极低，整个行星看上去就像一个冰雪星球。
当然这也取决于行星上水的含量，有的星球上有大片的海洋，这些水可能凝结成冰壳；有的星球上一点水都没有；但星球表面的气体微粒也会转化成冰的结构，因为当温度足够低时，气体就会凝华。
所以，温度是一个关键因素。行星的温度足够低，也意味着它更远离恒星。离恒星太近的话，是肯定不会有冰雪星球的。

But you also have to be careful about the structure of the atmosphere of the planet. I take an example like Venus. Venus is full of carbon dioxide and that warmed the planet. It's the greenhouse effect.
除此之外，行星的大气层结构也很重要。我们以金星为例，金星上充满了二氧化碳，产生了温室效应，导致金星表面的温度很高。

Well, if you remove this and you can bring gas that is cooling the planet as well. And that happened on Earth and the Earth had way more carbon dioxide in the past, because of the rise of life and a lot of production of oxygen. That was one of the big effects called the Great Oxygenation event.
The whole atmosphere of Earth has been transformed. And at that time the temperature equilibrium was dramatically changed, and the Earth became what we call a snowball.
So it was exactly the kind of icy planet you will encounter in the game, and that was a result of a dramatic change of the nature of the atmosphere of that planet.
当然，此外也有一些能使行星降温的气体。地球就是这种情况。过去，地球上的二氧化碳要比现在多得多。后来，随着生命的发展以及氧气含量的增加，地球上发生了名为「大氧化事件」的现象。
大气层的整体结构被彻底改变，地球的热平衡发生了剧烈变化，地球变成了我们刚才所说的「雪球」。
正如我们游戏中所遇到的（雅利洛-Ⅵ），这正是行星大气层结构剧烈变化所造成的。

So you see, there's so much possibilities you can play with. It depends really on the chemistry of the planet and the structure of the planet, and then of course, of the amount of energy which is radiating on the planet by the star.
So what has happened in the last 30 years is we have been exposed to a diversity of planetary system that no one would have imagined.
不难发现，关于行星的形态，有非常多的可能性。它取决于行星的化学构成、行星的结构，也取决于恒星辐射到行星上的能量。
过去30年来，我们探测到了无数不同的行星系统，它们的多样性超乎所有人的想象。

When you have a rocky planet, depending where the planet is sitting on the its orbit, you have a different scenario on the surface of the planet.
Take the earth, bring it closer to the sun. You're going to end up with one face of the Earth, extremely hot, so hot that you would melt the continent. So you end up with what we call a lava planet.
Now another case you can imagine, you take the earth and you make it much bigger, much bigger than the Earth, not one earth mass, maybe 5, 10 times the mass of the Earth. And you have a lot of carbon as well. So you have all this carbon on the planet, and then you have this higher mass, higher mass means pressure. The more mass you have, more pressure you have on the planet. When you combine the carbon on the pressure, you create diamond.
This is exactly how you create diamond on Earth. So this kind of a very massive planet you could imagine, this should be full of diamond.
假设有一颗岩石行星，它所处轨道的位置则会决定行星表面的不同情况。
以地球为例，如果地球比现在更靠近太阳，那地球面向太阳的那一面会变得非常炽热，炽热到大陆开始被融化。这时地球就变成了我们所说的熔岩星球。
我们还可以想象另一种情况，假如地球变大，大到超出现在很多倍，比如是当前地球质量的5倍到10倍，而且地球上还有很多碳。当你具备了大量的碳，以及更大的行星质量，更大的质量会产生更大的压力。质量越大，地球表面的压力就越大，碳在高压下会变成钻石。
地球上的钻石就是这么来的。由此，我们可以想象，地球就会变成一颗到处都是钻石的巨大星球。

Astronomy is a is a wonderful topic for research because we are studying a specific element which is the universe. And for us astrophysicists, the universe is our lab. And that's a wonderful lab because it's a lab that has so much possibilities, way more than any lab you can imagine on Earth.
For example, you can see through the time depending how far you look at.
You look back in time. You can look at objects which are just impossible to reproduce, like a black hole, which is an infinite point where everything is attracted.
You can look at objects that are extremely hot at the temperature that you will never, never think about.
You can look at energy event which is unique like a supernova again and again and again.
So you are looking at what's called the extreme boundary of the physics,
the coolest, the biggest, the smallest, anything you can get into the universe.
And that's wonderful.
天文学是一门很奇妙的学科。因为我们研究的课题比较特别——宇宙。
在我们天体物理学者看来，宇宙就是我们的实验室。而且它是一座完美的实验室，因为它存在无限的可能性，比地球上任何一座实验室都要丰富得多。
举个例子，只要你看得足够远，你的视线就可以穿越时间。
你可以回溯到过去的时间，观察到一些不可能再现的物体，比如黑洞。黑洞是一个质量无穷大的点，所有东西都会被它吸进去。
你还可以观察到极其炽热的物体，它们的温度远远超出你的想象。
你还可以一次又一次地观察到非常壮观的能量事件，比如超新星爆发。
可以说，我们在观察的正是所谓物理学的极限边界：最冷的，最大的，最小的——宇宙中存在的所有最极端的东西。

Possibly one of the biggest questions of the humankind is: is there any life outside the solar system?
Fermi paradox was half a joke when Enrico Fermi said, well, if there is plenty of life in the universe, so why don't we see it?
And actually the question is very profound in its meaning. It implied that life has to develop and to be able to to travel between stars and galaxies.
Maybe we are not able to see it. So if there is no life travelling between galaxies, it means that maybe there is a possibility that when life developed the capability to do it, it just stopped.
Just looking at the thermonuclear weapons we have on Earth right now. We have not the capability to travel between stars, but are we going to survive until we are reaching that stage? And that is what is behind really the Fermi Paradox.
宇宙便是如此奇妙万千，人类最关心的问题可能是：太阳系外有生命吗？
费米悖论来源于恩利克•费米一句半开玩笑的话。他说：“如果宇宙中真的存在许多生命，为什么时至今日，我们依然没有发现这些生命呢？”
其实，这个问题具有非常深刻的内涵。费米悖论暗示生命需要经过漫长的进化发展，才能够在星系之间旅行。
也许，我们只是无法看见这些生命而已。但是，如果星系之间确实没有生命在穿梭，那就意味着，生命止步在了发展出星际旅行能力之前。
比如我们，看看我们自己手上的热核武器，我们还没有能力在恒星之间穿行。人类能幸存到那个时候吗？这才是隐藏在费米悖论背后的真正含义。

Life may be common in terms of being started on other stars. But the development of life leading to a species that would be able to lift off from its planet may be extremely rare. And think about our stories: without this big asteroids falling on Earth, maybe this planet would be still populated by dinosaurs. And whether the dinosaur could have been evolving and go to the moon is not sure.
生命在宇宙中或许随处可见，但是，能够摆脱行星重力束缚的生命，可能极为少见。以我们的地球为例，如果小行星不曾撞击地球，也许现在地球的主人还是恐龙。恐龙是否会继续进化并登上月球？我们不得而知。

Maybe it's very rare, maybe we are the only life entity with the awareness of the knowledge of the universe in this Galaxy. So it's also something to think about and maybe to cherish our situation, our extreme situation, our responsibility on that matter.
So I think this Fermi Paradox is interesting in terms of philosophical sense because it asks the question of the meaning of our civilizations and the destiny of our civilizations.
At the same time, it demonstrates how beautiful is our destiny to be able to ask the question already.
人类的进化可能非常罕见，我们或许是银河系中唯一一个。了解有关宇宙的知识的族群，这一点值得让我们深思，也让我们要更加珍惜自己的文明。珍惜我们的特殊性，以及这个特殊性所肩负的责任。
所以我认为，费米悖论具有深刻的哲学意义，它启发我们思考人类文明的意义，以及人类文明的命运。
同时，人类得以提出这样的问题，也证明了文明的进化本身，是多么伟大和壮丽。

So whether we will one day get the answer?
I don't know. I tend to be optimistic and to be a believer to the kindness of humankind.
But we still have to face serious challenges as a global entity because we have only one place to live.It's this planet, nowhere else.
And we should really, as a global population, better learn how to address it together, to use it wisely if one day, we want to have any hope of our species to travel to other stars.
那么，我们能否最终找到费米悖论的答案呢？
我也不确定。不过，我还是比较乐观的，我愿意相信人性的善良。
当然，我们仍然面临严峻的挑战，因为我们只有一个家园。它的名字叫地球。
作为一个整体，我们应该团结起来，共同思考这个问题。这样才能终有一天，让我们人类的旅途能够抵达群星。