How to colonize a distant exoplanet, and most importantly, how to get there? Are there technologies for this right now? How to raise a child from a frozen embryo using a robot and a dog? Why is it better to plant genetically modified plants on an exoplanet? When will humanity be able to create a colony on Mars and why build a machine with insect intelligence? We talked about this with the famous Russian astrophysicist Boris Stern.
Boris Evgenievich Stern - astrophysicist, editor-in-chief of the newspaper "Troitsky Variant", Doctor of Physics and Mathematics, leading researcher at the Institute for Nuclear Research of the Russian Academy of Sciences and the Astronomical Center of the Physics Institute of the Academy of Sciences. Finalist of the 2014 Enlightener Prize for the book Breakthrough Beyond the End of the World. On the cosmology of earthlings and Europians”. Author of the science fiction book Ark 47 Libra.
Boris Evgenievich, astrophysics seems to be a field far from literature. Why did you start writing science fiction?
- Firstly, this area is not so distant. And I am far from the first. Let us recall the outstanding astrophysicist Fred Hoyle and his equally outstanding science fiction novel The Black Cloud. Or Carl Sagan, a wonderful planetary scientist who also wrote science fiction. From compatriots - Nikolay Gorkavy. Astrophysicists have made more science fiction writers than representatives of any other profession. I wrote something for a long time, but on the table. After I published a popular science book on the origin of the Universe, I wanted to realize my old idea: to write a book about the first interstellar flight. Many have written about this - a topic beaten to the point of disgrace. But if you stay within the framework of the laws of nature and modern data on other planetary systems, then the idea takes on a completely different meaning: overcoming interstellar distances in itself becomes the hardest drama without any wars and evil aliens. The idea appeared somewhere in the 1980s. I have been carrying it for more than a quarter of a century, and now, finally, I have realized it in the form of the book "Ark 47 Libra". In general, I do not consider myself a writer - I am a physicist.
Your new book, Ark 47 Libra, published last year, is about colonizing a planet suitable for life. Tell us about your thoughts on this idea
- The nearest exoplanet, which may be suitable for habitation, is located about 20 light years from us (I wrote in a book about 60 light years, but in fact there are closer). It takes thousands of years to get there at best. And this must be understood absolutely clearly - it is absolutely unrealistic to get there in less time. Therefore, there can be no talk of any manned flights. To begin with, let's say you can send a probe that will collect the necessary information about the planet. It will be received by distant descendants, not those who will send the probe. And this is a huge problem. Everything related to inter-star flights rests not on technical issues, but on psychological ones. To implement such an idea, altruism must win, a powerful social vector must be formed.
Nature has in store for us a gift recently discovered.
The planet Proxima b revolves around the closest star, Proxima Centauri, which is just over four light years away.In principle, it is at the correct distance from the star, so liquid water could exist on it. True, the star is not suitable - too active, so the planet is hardly suitable for life. But she is a perfect target for the first interstellar probe. There is a project of a tiny probe - 1–2 grams - which will fly there in twenty years (the project is called StarShot; was announced on April 12, 2016 at a press conference held in New York by Russian entrepreneur Yuri Milner and astrophysicist Stephen Hawking, in the project also included Facebook CEO Mark Zuckerberg; the estimated cost of the project is between $ 5 billion and $ 10 billion, the initial funding - $ 100 million - he has already received - NS). But, alas, the project is completely unrealistic and hopeless, in my opinion. It's just a jumble of fantastic assumptions.
But, apparently, on a flight project for a time longer than the life of a generation, you will not make a good PR effect. In fact, a flight over 200 years is much more realistic. For such a travel time there, you can launch a normal probe that can control its trajectory, fly close to the planet, take good pictures and send them to Earth. No hopeless technical problems other than motivation. While we are not yet morally ripe for this. I really want to see the result during life, that we are descendants?
If we talk about technical issues, what is needed to fly to a distant planet?
- If we are talking about “flying to a person” (for example, in the form of a frozen embryo), then only colonization can make some sense. And this is even more difficult in terms of the same motivation. The book is, in general, just about this - not so much about technology, but about psychology and why all this is needed. If we talk about technical things, then colonization is quite possible and people, as you know, have been thinking about it for a long time. One of the first concepts of a spacecraft of this kind is the so-called explosive, which is propelled by exploding hydrogen bombs. Moreover, in this project, very famous people lit up, for example Freeman Dyson. True, this was back in the 1950s. But, apparently, neither Dyson nor other major scientists took these ideas seriously, only as a kind of fun. The minimum mass of an interstellar explosion is 5 million tons, and it will also fly for thousands of years. But there are other, more real projects.
For example, using an ordinary uranium reactor as a power source for a ship. If you count everything there carefully, you can accelerate the ship to about one hundredth the speed of light. In this case, we will reach the planet, which is 20 light years from us, in 3-4 thousand years. In the "Ark" just a similar ship is described - just a speculative concept, but not completely stupid. This, of course, is not a ship, but a caravan of elements connected by thin threads tens of kilometers long - the payload must be kept away from the reactor, the engine is in front, the biomaterials in magnetic shielding are far behind. Optimal mode - the reactor and engine operate at minimum power all the time. The reactor's fuel elements are thin kilometer-long uranium rods that slowly extend through the core. The acceleration is negligible. One of the inevitable details is the huge radiators. The main problem, which now seems daunting, is that all this must work for thousands of years. But this does not contradict the laws of nature.
This, of course, is very long. If we are talking about such long time intervals, then why do we need to accelerate the ship at all, because it is more expensive. Let tens of thousands of years fly by?
- This is important, because for tens of thousands of years we will not be able to protect the biological materials that we carry on this ship, but for a shorter period of time we can. Any biomaterials for too long a period of time would receive such a dose of cosmic radiation that they simply would not survive.Of course, we are not talking about people, but only about fertilized eggs or embryos that have just begun to divide, which can be frozen, for example, in liquid nitrogen. And then place them in a superconducting solenoid that protects them with its magnetic field from cosmic rays. Egg freezing technologies are known to be widely used today.
But where will these future people fly, how to make a distant planet habitable?
- Suppose there is already water in a liquid state on the target planet, but there is no life and oxygen. First of all, our task is to release to the planet one of the most unpretentious and widespread organisms: blue-green algae, that is, cyanobacteria. In about a hundred years, due to their activity, a little oxygen will appear in the atmosphere. At this stage, lichens are already sown, which almost do not need oxygen, but "digest" the soil. After another couple of hundred years, grass and moss are sown into the resulting soil. And then, after some time, higher plants are planted in the humid equatorial zone.
The best oxygen producers on Earth are rainforests. On an alien planet, I suppose, it will be more effective to plant genetically modified plants, possibly herbaceous plants, which will intensively release oxygen. For thousands of years, such forests will enrich the atmosphere with oxygen by no less than 20%. Of course, all this is just speculative reasoning, and there may be a lot of objections, but I do not pretend to be more. In this case, I only offer ideas, maybe not entirely idle, but nothing more. For example, even finding such a planet, choosing it correctly is another story. In order to do this, appropriate technologies are needed. They are not there yet, and they will not appear in the next decades. In general, this would have been possible in the foreseeable future, if the plan to create space interferometers had not been buried: the European project called "Darwin" or the American TPF. These projects were very complex and expensive - therefore they were abandoned - but in this way they cut off the opportunity to find a livable planet for decades.
If we continue talking about colonization, then who will be engaged in the crops?
- Of course, robots. In terms of intelligence, they should be roughly like insects. It'll be enough. So far there are none, but this is not something fantastic either. Now a breakthrough in robotics is going exactly in this direction - the development of primitive artificial intelligence. For example, today there are very good developments in the field of pattern recognition. There is such a concept as Deep learning - these are systems similar to human neural networks, and, importantly, these systems can be trained. Moreover, the trainer does not know what is happening in the electronic models of neural networks in the learning process. So far, these are only the beginnings of future robots, but the basis is already there, and, I think, within the next decades we will be able to create creatures of the intellectual level of insects. This will be a giant breakthrough. In the book, ten tons of finished robots and 30 million chips were brought to the new planet for those whose bodies will be created from local materials. This is just a fantasy.
Let's say that crops have already risen on our exoplanet, trees are growing and there is enough oxygen in the atmosphere to breathe. What's next? How to grow humans and animals from frozen fertilized eggs?
- I think that the problem of raising a baby mammal from a fertilized egg in an artificial uterus can be solved in the coming decades or even a decade. This is if we talk about raising animals, there is no talk of a person yet, because, among others, a number of ethical problems arise here. Although they do occur with animals. Nevertheless, the latter can be raised without parents - using all the same robots.In order to raise people, the plot of the "Ark" assumes a combination: a service humanoid robot, a "human replica" and a dog. A human replica (according to the book - NS) is a technique that can reproduce an electronic model of a particular person, built on trained neural networks. An artificial neural network must undergo many years of training: to listen, recognize and imitate the person next to it. And then, thousands of years later - to act as a hologram of this person, adopting his appearance, logic, intonation, and reactions. According to the plot, children are brought up by the replicas of caring parents, then teachers, then professors. And yet this is not enough. The missing link, in my opinion, might be the dog (I was just watching my dogs interact with my grandchildren). Here, too, not everything is so simple, there are many nuances, I discuss them in the book. A dog can give that part of the living heat that is necessary for each of us and that the robot cannot give.
If you do not hope that humanity will become more reasonable in the foreseeable future and will spend a lot of time, effort and money on such a project, then what can you offer as a motivation? Say, mining, as shown in many science fiction films, for example in Avatar?
- Alas, of course, there are no values that would be economically profitable to transport to Earth through interstellar distances (but for transportation from Earth, there is such value - this is life). In the solar system - maybe, but it must also be some absolutely incredible value of things. Most likely, there are none either. Therefore, one has to rely only on the growth of self-awareness of mankind.
Have you considered the psychological aspect of cohabitation of a small group of people on an unfamiliar planet? Will they kill each other?
- There are examples - of course, they are not as long as living together on a distant planet all their life, but nevertheless. Say, Antarctic and polar expeditions or small colonies of settlers who came to America in the 17th and 18th centuries. A survival situation usually mobilizes people and holds them in their hands. One of the heroes of my book discusses why there are no boors, crooks and fools on Mars. And, as it were, he answers to himself - because there are no good conditions on Mars: there are no rivers, forests, you cannot breathe freely. But when all this appears, there will probably be boors, and crooks, and fools. In difficult conditions, people are mobilized, they have a common goal. At least this, it seems to me, can be hoped for.
According to your forecasts, when will humanity really be able to organize a colony on Mars, and when - on distant exoplanets?
- In the case of Mars, I think this may happen in the next decades. Or it will never happen, depending on which global trends win. In the case of exoplanets, for at least one to two hundred years. And then, if the civilization will develop and not degrade. But now I'm talking again about the technical components. As for all the same notorious motivation, it is very difficult to say here, because serious work of our biological species on itself is needed. Whether and when this will happen is unknown. As for the foundations for such motivation, then everything is simple: a person lives little, but gives offspring and the race continues. It is not a fact that human civilization will survive for a long time. Stephen Hawking once said that humanity is doomed without expansion into space. Yours truly, and many others, share the same point of view. But if human civilization manages to create a colony on another planet, it will be a descendant civilization with an independent destiny, which can give its offspring on new planets. So life and mind will be able to ensure their existence for tens or hundreds of billions of years. This is a global issue related to the place of intelligent life in the universe.Who knows, maybe intelligence is the best thing in her.